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3 CONTENTS Introduction l Acknowledgments l Summary l Lake of the Woods Area General Statement Location Mines of West Shoal Lake Whitefish Bay Locality Rush Bay Locality Mines near Bald Indian Bay, Andrew Bay and Witch Bay Mines East of Kenora Rainy Lake Area The Geological Succession at Bears Pass East Shoal Lake Mines General Geology Mines of East Shoal Lake Area Upper Seine River Area Manitou Lake Area General Geology Mining Proper! ies l )rvden Area General Geology Mining Properties ILLUSTRATIONS Mikado mine. Ba*; bay. \\'est Shoal lake Mikado mine looking towards Bag bay, West Shoal lake ()pen-i ui. l *i\ inpia mine Souths e-t -haft. Regina mine, showing shear zone Gulden Morn mine. Rush bay, Lake of the Woods Point on ku-ti hay. Lake of the Woods, north of Golden Horn mine Sultana mine. Bald I.idian bay, Lake of the Woods Open-cut. C ri iv. n Reef vein, Sultana mine Coutchiohing sediments along the axis of the Bears Pass anticline Quartxite. * Mive tr.ine MAPS AND DIAGRAMS Key Map Showing Locations of Gold Deposits, Districts of Kenora and Rainy River,.facing 1 Mikado ami ' Hvmpia Gold Mines, District of Kenora facing 4 Cameron Island ' -old Mine, District of Kenora facing 10 Regina Gold Mine. District of Kenora facing 12 Sultana and ()phir Gold Mines, District of Kenora facing 16 Bears Pass Area. District of Rainy River facing 22 Foley Gold Mine and Stagee Prospect, District of Rainy River facing 24 Golden Star (iold Mine, District of Rainy River facing 27 Olive Gold Mine. District of Rainy River facing 28 Elizabeth Gold Mine, District of Rainy River facing 30 Sawbill and Hammond Reef Gold Mines, District of Rainy River facing 32 Laurentian and Big Master Gold Mines, District of Kenora facing 36 Sakoose Gold Mine, District of Kenora facing 38 COLOURED GEOLOGICAL MAP (In pocket at back of report) Map No. 34h Contact Bay (Bonanza and Redeemer) Gold Mines, District of Kenora, Ontario. Scale, 200 feet to the inch. [i]

4

5 GOLD DEPOSITS OF KENORA AND RAINY RIVER DISTRICTS By E. L. Bruce Introduction Gold was discovered in 1871 at the Huronian mine in Moss township, about 75 miles west of Port Arthur. Since that time, veins have been worked for gold at several places, and some, for a time, returned profits to the operators. On the whole, however, gold mining in this region has, for various reasons, not been successful. Comprehensive reports dealing principally with the general geological succession of the region west of Lake Superior have been published by the Geological Survey of Canada. 1 Reports dealing chiefly with the mineral deposits have been published by the Ontario Department of Mines, 2 and, in addition, descriptions of individual occurrences have appeared from time to time in technical journals. It is the purpose of the present report to record recent develop ments and to discuss in detail some of the more important gold occurrences. No attempt has been made to review the general geology in any area, with the exception of the locality at Bears Pass in the Rainy River map-sheet, where some detailed areal mapping was done on account of the controversy there has been concerning the geological succession. Detailed maps have been made around many of the mines in order to show the relation of the ore bodies. Acknowledgments Every assistance possible was rendered by all those interested in the mineral deposits, and the writer wishes to acknowledge very gratefully the special kindness and hospitality of Colonel H. A. C. Machin, of Kenora; J. F. Caldwell, Winnipeg; the officials of the British Canadian Mines, Limited; and William White, of Hilly Lake. The writer's party consisted of H. H. North, R. H. Cleland, and G. D. Furse, all of whom were exceptionally capable and enthusiastic. The greater part of the credit for the detailed mapping belongs to these three men, as well as some of the geological data concerning the Dryden and Dyment areas, which were finished after the writer left the field. J. W. Greig, of the Geophysical Laboratory, Washington, was also a member of the party for part of the season. The descriptions of the Elizabeth and Harold Lake mines are entirely from his notes, as well as a considerable part of the details concerning the Sawbill and Hammond Reef properties. In addition, many helpful suggestions concerning the geological problems of the Rainy Lake district were received from him. Summary Detailed examinations show that the failure to establish profitable gold mining in the region west of Lake Superior is due to a combination of circumigeol. Surv. Can., Vol. I, pt. CC, 1885; Vol. X, pt. H, 1897; etc. 2Ont. Bur. Mines, Vol. IV, 1894; Vol. V, 1895; Vol. VI, 1896; Vol. XX, 1911; Vol. XXI, 1912; Ont. Dept. Mines, Vol. XXX, pt. 2, [1]

6 stances. In many cases, the veins developed were too small or too low in gold content to merit the amount of time and money expended upon them, and proper advice to the operators would, if followed, have saved much loss. On many claims, the work was done in a haphazard way, and usually the installation of a mill was undertaken long before there was any need of it, or any reasonable grounds for believing that a mill would be necessary at all. As a result, the available funds were exhausted before the vein had been fairly tested. Mining methods not suited to the ore bodies are common, and at many prospects the expenditure on surface plant was not warranted by the stage reached in under ground development. Some mines apparently were making profits in a small way, but ambitious directors attempted to make them into large mines without regard to the character of the ore bodies or the amount of ore blocked out, and the result was disastrous. There was lack of knowledge of the types of veins, wrong conclusions regarding structure, and many other avoidable errors that made success almost impossible. In addition to the factors enumerated, much gold was no doubt stolen from some of the high-grade pockets, and there were also unavoidable losses, since methods of treatment of gold ores had not reached the perfection they now have. Cyanidation was only beginning to be used, and the modern method of fine grinding had not been thought of. As a result, the losses of values in tailings no doubt were fairly high. It is doubtful if any prospective gold field could be successful in the face of such adverse conditions, but the question arises as to the possibility of working the deposits under modern methods with careful management and with the best of technical direction. A review of the geological occurrence of the goldbearing veins of the various properties will show the following features: 1. High-grade shoots of ore were found in several veins in Western Ontario, but without exception the greater part of the vein material was low-grade and the average of rich pockets and low-grade vein matter together would be an ore of only medium grade. Hence mining development should be kept well ahead of milling, so that the parts of the vein where the gold content was excep tionally high could be used to raise the grade of the parts which were low. This evidently was not done in any of the Western Ontario mines. 2. Ore shoots in many veins were found to be close to contacts between granite and greenstone, and the resulting ore body was therefore chimney-like in shape. 3. Veins are better defined in granite than in greenstone, but granitic wall rocks offer but little opportunity for impregnation by vein solutions. As a result, the values in veins cutting granite are confined almost completely to the quartz. Hence, though the vein proper may be fairly high in gold, weight must be given to the fact that only the vein carries gold and that if it is not wide enough to make possible mine workings entirely in quartz, the average value of the vein will be diminished in proportion to the amount of barren rock with which the vein material must be diluted in mining. On the whole, the amount of replacement or impregnation of country rocks along the veins, even where they are in schistose greenstone, is not very great, and this seems to be the most unfavourable feature of the greater number of the veins seen. It is evident that the acidic intrusions carried gold in considerable quantity, so that locally, at any rate, the veins are of commercial grade, but probably from lack of widespread fracturing previous to the period of vein filling sufficient space was not prepared for the solutions to penetrate far into the rocks adjacent to the vein fissures.

7 Taking account of the amount of gold produced from this region under adverse conditions and the widespread occurrence of auriferous veins, many of them containing lenses of high-grade ore, it seems very probable that with proper management and foresight some of the gold deposits of Western Ontario may be developed into paying mines. Lake of the Woods Area General Statement The oldest rocks of the Lake of the Woods basin, as described by Lawson, consist of the Keewatin, a great complex of schists of various types and different origin, and of basic effusives. The Keewatin is intruded by granite, which on the original map was differentiated into two types. Many varieties occur, but there seems to be no satisfactory evidence to show whether they belong all to one period of intrusion or to many. Minor changes in areal mapping were made by A. L. Parsons, 1 but on the whole, the original work of Lawson still remains a satisfactory delineation of the geological succession. Location The localities in the vicinity of the Lake of the Woods where gold deposits have been worked fall naturally into four groups: those on the shores and islands of West Shoal lake, including the Mikado, Olympia, Tycoon, Cornucopia, Sirdar, and Cameron Island; the Regina mine on the south shore of Regina bay; the Sultana, Ophir, Gold Hill, etc., near Bald Indian bay; and the group north east of the Lake of the Woods, to which belong the Scramble, Champion, Hilly Lake, etc. In addition to these, there are two or three isolated mines, such as the Golden Horn on Rush bay and the Wendigo, north of Witch bay. Mines of West Shoal Lake Mikado. The largest producer of gold and the best known mine of the West Shoal Lake area is the Mikado, which was discovered in 1893 and operated continuously up to Since that time, it has had periods of activity in , in and again in The gold production from this property is reported as approximately 8500,000. Pockets of extremely rich ore occurred in the vein, and it is reported and apparently is true that a great deal of gold was stolen by miners during the early days of the mine. Hence, it is generally believed that the production is much larger than the amount reported, but no estimate can be arrived at, as the amount of gold stolen may be much exaggerated. The Mikado is located on the south shore of Bag bay, West Shoal lake. By boat it is between forty and forty-five miles from Kenora, but a shorter portage route can be followed by Ptarmigan bay. The winter road from Kenora is about thirty-five miles in length. From the Canadian Pacific railway, at a point about twenty-five miles west of Kenora, the distance south to the Mikado mine is only twelve miles in a straight line. During periods of normal water level in the Lake of the Woods, launches and shallow-draft scows can pass up Ash rapids into Shoal lake, and transportation is a comparatively simple matter. In addition to the route by way of Kenora, Shoal lake may be reached from Winnipeg by the railway of the Greater Winnipeg Water system, which terminates at Indian bay on the west side of Shoal lake. Lawson's map of the northern part of the Lake of the Woods, which!qnt. Bur. Mines, Vol. XX, pt. l, 1911, pp ; Vol. XXI, pt. l, 1912, pp

8 accompanies his report on that district, 1 shows the rocks in the vicinity of Bag bay as hornblende schists, altered traps, and some chlorite schists, all of igneous origin, intruded by a great boss of granite. He notes also felsitic intrusions in the schists concentrically arranged with reference to the granite boss and, he believes, genetically related to it. 2 Parsons has described the rocks as "trap which has to a large extent been altered so as to form hornblende and chlorite schists." Intrusions into the trap have been called by him felsite and granite. 3 On the whole, the Keewatin rocks at the Mikado are fairly massive. Schistose structure where developed is local, and excepting along some of the veins or near the intrusions, foliation is not distinct. On the high ridge south of the shaft, the rocks are massive greenstone with distinct ellipsoidal weathering. A thin section shows the rock to consist chiefly of a felt of light-green amphibole in somewhat elongated crystals with a small amount of quartz lying between the fibres. It is, no doubt, an altered basic lava. The main granite mass which intrudes the Keewatin consists of mediumgrained pinkish rock with quartz, feldspar, and hornblende distinguishable in Mikado mine, Bag bay, West Shoal lake. the hand specimen. Under the microscope, a specimen near the contact with the Keewatin at a point between No. l shaft and No. 2 shaft is biotite granite. The original minerals are quartz, orthoclase, microline, a plagioclase probably near oligoclase in composition, and large foils of biotite. The feldspars have been considerably altered with the production of sericite and kaolin, and the biotite also shows the beginning of alteration. A sample of granite from the dump at the Sirdar shaft, which is northeast of the Mikado and a considerable distance from any exposures of Keewatin rocks, consists of orthoclase microcline and acidic plagioclase with brownish-green hornblende. Sericite and kaolin are alteration products. Lawson describes the granite of this area in general as a biotite granite. There are, no doubt, slight variations in composition in various parts of the mass, so that biotite occurs in some places and hornblende in others. Both the Keewatin lavas and the granite that intrudes them are cut by dikes of red pegmatitic granite. One of these is exposed as an oval mass at shaft No. 2 and extends almost continuously westward to the well-marked!geol. Surv. Can., Vol. I, pt. CC, Ibid, p Ont. Bur. Mines, Vol. XX, pt. l, 1911, p. 164; Vol. XXI, pt. l, 1912, p. 192.

9 dike at the main shaft of the Mikado. This dike can be followed to the deep drift-filled valley west of the buildings. On the ridge west of the valley, it splits into two tongues which taper out on top of the ridge. On the western side of the ridge similar rock is exposed at the tunnel entrance, and it seems likely that the dike is continuous, but that the top of the ridge is above its upper termination. Rock from No. 2 shaft examined microscopically is found to be composed almost entirely of light-coloured minerals: quartz, orthoclase, microcline, and acidic plagioclase, with a few shreds of muscovite. The feldspars are much altered, the original crystals being replaced by foils of sericite. Muscovite has been recrystallized into sericite, so that only shreds of the original crystals are left. As a result of the alteration, the rock in the hand specimen looks porphyritic. The apparent phenocrysts, however, are merely the unaltered quartz of the granite lying among the altered feldspars. Specimens taken westward along the dike have similar characteristics, and some are micrographic in texture. The south tongue west of the shaft is a typical acidic granite with abundant quartz, microcline, orthoclase, and acid plagioclase, with the usual alteration products. A red facies of this rock is a strikingly graphic intergrowth. Mikado mine looking towards Bag bay, West Shoal lake. of quartz and orthoclase. Plagioclase is present, but is subordinate in amount to the other two constituents. Sericite is scattered through both types of feldspar. This rock probably represents the last liquid portion of the intrusion. Coleman interpreted the relation of the granites correctly from specimens examined microscopically. His description is as follows: One [specimen] consists of rather shattered quartz, little orthoclase and much plagioclase, often idiomorphic and having zonal structure with a considerable amount of biotite. The other specimen is red in colour.... The feldspar is mainly orthoclase or microperthite and is greatly mtergrown with quartz as micropegmatite and the small amount of mica present is colourless. This perhaps a dike rock penetrating the other granite. 1 Two veins on the Mikado property have produced ore. The main vein at shaft No. l strikes N. 300 W. and dips 85 0 N.E. The width of the vein varies from six feet down to stringers in some parts. Coleman states that the width, where exposed on the surface before mining was commenced, was six JOnt. Bur. Mines, Vol. V, 1895, p. 103.

10 feet and that it was exposed across the outcrop of rock for a distance of one hundred feet. 1 The strike of the vein should carry it across a knoll of greenstone 300 feet southeast of the shaft, but there is no sign of it on the surface, although the underground workings must have followed the vein much farther than that. A pit, 1,600 feet southeast of the shaft, shows a vein that carries some values, but the strike would carry it to the west of the shaft. The physical character of the vein differs very considerably at different places. Along the inclined shaft from the 4th level down to a point twenty-five feet vertically above the 7th level, the vein is narrow, shows little quartz, and has not been stoped. Mine plans, however, show that to the south of the incline the vein has been stoped. At the point mentioned above, the shaft passes from the basic rocks into a granite dike. The vein widens to an average of five feet, which is mostly quartz. The granite extends northward from the shaft along the 7th level only ten feet, but the vein maintains a good average width for a distance of sixty-five feet. From that point to the foot of a winze that comes down from the 4th level, 275 feet north of the shaft, the vein consists only of a few small lenses of quartz and some stringers of calcite. At the winze, the drift shows a lens of quartz a foot wide, which swings to the west and flattens from the normal dip of 85 0 N.E. to a dip of 60 0 N.E. The drift has been deflected 10 0 to the west, but from the winze northward for a hundred feet there is only a crack to follow. There, a zone of quartz stringers two and a half feet wide, of which quartz forms about one-quarter of the whole, comes in from the west and may be the continuation of the lens that swings westward out of the drift at the winze. Four hundred and fifty feet from the shaft, or seventy-five feet north of the point where the stringers appear, gold can be seen in the vein material, but the vein is still a series of stringers. Four hundred and sixty-five feet from the shaft, the vein passes into granite and becomes wider and better defined, so that at 500 feet a lens of quartz on the hanging-wall side has a width of sixteen inches and on the footwall side there is another zone of ribboned quartz also sixteen inches in width. At 550 feet on the hanging-wall side and 560 on the footwall, the vein passes into greenstone and at once narrows to stringers. At 580 feet on the hanging-wall side and 610 on the footwall, another granite dike is encountered, which is still the wall rock at the end of the drift at 640 feet. The vein in the dike again assumes a well-defined character, and at the face of the drift shows two lenses of quartz similar to those at 500 feet. This detailed description of the type of the vein on one level is given to emphasize the fact that has impressed every one who has examined the mine, that the vein is wider and more continuous where the wall rocks are granite than it is where it lies in greenstone. No definite difference was noted in the quartz in each type of rock. In general, it is white to bluish-white and translucent. Much of it is very definitely ribboned in structure, apparently due to replacement of somewhat schistose rock parallel to the main fissure. The values carried by the Mikado No. l vein cannot be fairly arrived at. The production of the mine in its early days was considerable, and the value of the ore must, in places, have been phenomenal. The rich ore shoots, however, were entirely stoped out with no records of the values obtained per ton, and it was perhaps impossible to arrive at the true values on account of the amount of high-grade ore that was stolen. There is, therefore, no information as to what parts of the vein were most productive, but it seems likely that that part which was removed by open-cut methods was high-grade material. In that JOp. cit., p. 50.

11 part of the vein, the wall rocks are granite, the vein cutting across the big pegmatite dike which is shown on the map. Whether the whole length of the vein in the pegmatite carried high values or only that part near the contacts of granite and greenstone cannot at present be determined on account of lack of data. It is clear, as pointed out above, that the vein improves physically on passing into granite country rock, but there may be some doubt that the values are as high where the vein is in granite as they are where the walls are greenstone. An assay of one sample taken from the vein on the 7th level where the walls are granite gives Si.40 per ton, 1 whereas a short distance along the vein where the walls are greenstone, gold is visible in the quartz, and no doubt the average gold content is considerably higher. The following facts concerning the upper part of the Mikado vein are given by Coleman. In the granite one finds a distinct footwall on the west side, but the vein matter seems to push out irregularly towards the east, no defined wall being seen, so that the full width of the deposit could net be very satisfactorily estimated. Ore carrying free gold is found perhaps fifteen feet east of the footwall. The quartz carries an unusual number of sulphides including pyrite, chalcopyrite, galena, molybdenite and bismuthinite.... Fine specimens of gold are frequently found in the quartz, and sometimes also in the altered granite east of the quartz proper. At the time of my visit an open trench was being cut along the top of the vein.... The first run of 297 tons of ore yielded 969 ounces of gold, or ^48.94 per ton. 2 W. E. H. Carter writes as follows: The ore shoot continues down to the lower levels, but there the vein passes entirely out of the granite country which in the upper levels it either cut through or was in contact with, and enters the trap. A drop in values accompanied the change, so that latterly ore running fts.oo or less per ton, was the best obtainable.... During 1901, for a period of eight months, the ore milled averaged in value 3.14 per ton, the total extraction by amalgamation followed by cyanidation of the tailings amounting to 87 per cent. For the next three months the ore ran per ton and extraction increased to 91 per cent. 3 The statement concerning the passage of the vein entirely into trap is, of course, true only of the part of the vein in the workings along the shaft, the incline of which carries it away from the granite-greenstone contact. No. 2 vein was described as a fissure of only two to three inches in width on the surface, which attained a width of two to three feet in depth. It cannot be seen at present. 4 It was undoubtedly rich in gold, and there is the same close relationship of the high values in it with the red pegmatitic facies of the granite. The workings and plant of the Mikado have been fully described in previous reports. Development work in 1922 was confined to sinking the vertical shaft. The old inclined shaft goes down not on the dip of the vein, but pitching at an angle of 30 0 to the southeast along the vein. It is hard to understand why it should ever have been sunk in that way and why development work should have been carried so far to the southeast. It seems plain that the main ore shoot was along the intersection of the vein with the pegmatite dike and that contact should have been the one to be thoroughly explored. It may be that other shoots were found where the vein crosses other dikes to the south. Thorough underground exploration may open up other ore shoots, as it seems unlikely that the vein should be entirely low grade below the exceptionally JA11 assays for this report were made at the Provincial Assay Office. 2Ont. Bur. Mines, Vol. VI, 1896, p Can. Min. Jour., Vol. VII, 1904, p Ibid, p. 120.

12 8 rich shoot which was found at the surface. Even should ore be found, it will require considerable development work to put the mine in working condition. Olympia. The Olympia lies directly south of the Mikado on Helldiver bay. The Keewatin rocks are continuous with those of the Mikado, but are slightly different in character. At the vein north of the mill, the rock is a greyishblack, fine-grained, granular rock of fresh appearance. Under the microscope, it is found to be ophitic in texture and of medium grain, containing quartz, lath-shaped plagioclase feldspar, and pleochroic green hornblende. The rock is a quartz diorite. It is possible that the hornblende is secondary and that the original rock was diabase. At the west tunnel, the rock has a bladed appearance and a satiny lustre. It differs from the rock just described in having no quartz and in the abundant development of serpentine, by the alteration of the horn blende. The knoll of rock at the shore of Helldiver bay east of the mill is made up of a dark rock in which are phenocrysts of a greenish mineral. The alteration of the phenocrysts is so complete that they do not appear as individual minerals under the microscope, but they were probably originally feldspars. The ground mass consists of lath-shaped plagioclase and hornblende, perhaps formed from pyroxene. If so, this rock was a diabase porphyry. Its relations to other rocks are not known. Coleman mentions a similar rock on the shore of Snake bay, Lake of the Woods. 1 No granite occurs anywhere near the workings, but a narrow tongue cuts the basic rocks between the Mikado and Olympia, as shown on the map accom panying Parsons' report of This tongue does not cross the trail between the Olympia and Mikado properties. The vein at the tunnel entrance north of the mill consists of twelve to fifteen inches of milky quartz with only a small amount of pyrite. The strike is nearly east-west, and the dip is 45 0 N. At the top of the shaft the width of the vein is considerably greater, and Parsons states that at the intersection of the shaft and tunnel the width is six feet. 2 The tunnels and open-cuts next to the east follow a zone of crushing which has been thoroughly impregnated by sulphides. A somewhat similar shear zone occurs at the eastern tunnel. It strikes northwest and dips 80 0 E. In the shearing planes, veinlets of quartz having thicknesses up to a quarter of an inch have formed and are spaced approximately an inch apart. The quartz is glassy. Pyrite is present but occurs sparingly. The development consists of a tunnel immediately north of the mill driven to intersect the shaft sunk on the top of the hill. A tunnel immediately north of the cabin was driven northwestward for a considerable distance and stoped up to the surface. The length is stated by Parsons to be 400 feet. During 1916, a tunnel was driven forty feet northward into the hill near the end of Helldiver bay. A well-built grade for a tram runs from the tunnel to the mill. No work has been done on the property in recent years. The production of gold is recorded as S2,101 during 1912 and a small amount from the operations in Cornucopia. The Cornucopia occupies the whole of Cedar island which lies close to the west shore of the point extending northward just west of the Mikado. The vein is almost completely covered, but seems to be a zone of quartz stringers in pyritized greenstone. A zone of similar character outcrops at the iqnt. Bur. Mines, Vol. VI, 1896, p Ibid, Vol. XX, pt. l, 1911, p. 162.

13 water's edge on the north end of the island, and the strike is about southwest. On the dump, pyrite and chalcopyrite occur with quartz. Assays of quartz taken at random from the dump gave a value of S13.60 in gold. In the report of the Ontario Bureau of Mines for 1896, : two veins are mentioned, one northwestsoutheast with a width of three to four feet and one northeast-southwest with a width of three feet. The veins are very irregular. A gold recovery of S l,560 is recorded from this property. Open-cut, Olympia mine. Tycoon and Sirdar. The Tycoon situated on an island in Bag bay, north of the Mikado, and the Sirdar on the mainland, northeast of the Mikado, both lie in the granite area. At neither shaft is there any vein to be seen, nor is there any quartz on the dumps. It is evident that both of these properties were operated only on account of their proximity to the Mikado. Cameron Island. The rocks of Cameron island are, first, basic rocks which include fine-grained greenstones and coarser amphibolites, and, second, porphyry dikes cutting the basic rocks. The amphibolite in the hand specimen consists of elongated lustrous black needles of amphibole. Under the microscope, VI., p. 50.

14 10 these are found to be actinolite, and there are also brown crystals with a more nearly equidimensional habit. These may be original basaltic hornblende, whereas the green variety may be largely the result of alteration. Pyrite is present in considerable quantity replacing the amphibole. The porphyry is a greyish porphyritic rock that occurs as dikes of con siderable width. The microscope shows phenocrysts of acidic plagioclase and perhaps orthoclase. The groundmass is feldspar quartz and biotite. Sericite has replaced a large part of the feldspar individuals. The ore consists chiefly of sulphides, which occur in several distinct zones, recognized on the surface by their rusty weathering. Parsons had an opportunity to see these underground, and his description is as follows: There are in all seven veins on the island, with a general strike N. 45 C E. On the east side of the island a tunnel has been driven about sixty feet, cutting two of these veins. About the centre of the island a shaft has been sunk 133 feet and two levels have been opened up, with about fifty feet of drifting on the first level and 220 feet on the second. In the second level the main vein averages about four feet in width, the hanging wall is well marked, but the footwall is not distinct though there is a well-mineralized contact zone. The vein material is quartz, with schistose bands which consist largely of chlorite. The metallic minerals are pyrite, pyr rhotite and chalcopyrite. 1 The sulphides seem to be without exception gold-bearing, so that samples are uniform in value. A brick from a mill-test of five tons of ore gave: Gold S47.81 Silver ounces. 2 A rather complete plant, including a chlorination furnace, was installed on the property, but everything of value has been stolen, and even some of the lumber has been removed from the shaft-house. Whitefish Bay Locality Regina. The Regina mine is situated on the south shore of Regina bay, a part of Whitefish bay, Lake of the Woods. This mine was one of the larger producers of the district. Discovered in 1894, it began producing in the following year and was operated continuously to October, 1899, and again for short periods in 1902 and The mine was being dewatered once more during the summer of There seems to be some doubt about the total production. In the Thirtieth Annual Report, Ontario Department of Mines, Part II, it is placed at 500,000; but an article on the mines of Ontario in the Journal of the Canadian Mining Institute for states that it was slightly over 200,000. The rocks at the Regina consist of altered basic lavas intruded by a boss of granite. On the knoll of rock exposed, east of the Hayfield, ellipsoidal weathering is well developed. This rock is made up entirely of a very fine grained felt of serpentine. On the ridge south of the main shaft, the rock is a fine-grained aggregate of slightly pleochroic serpentine, quartz, and some magnetite which has probably separated out from the original iron-bearing minerals during the formation of the serpentine. Schistosity is not commonly developed, and the intrusion of the granite seems to have taken place with very little disturbance. South of the shaft, the contact between the two rocks is remarkably sharp with but little apparent effect produced upon the greenstone by the intrusive. Eastward along the summit of the greenstone ridge south of the tunnel, there is a contact zone with an intimate penetration of the older!ont. Bur. Mines, Vol. XX, pt. l, 1911, p Ibid, Vol. XXV, pt. l, 1916, p Vol. VII, page 136.

15 11 by the younger rock and the inclusion of fragments of greenstone in the granite. Here, also, there has been some modification of the texture of the greenstone producing a coarser-grained rock than is usual. The granite shows many variations, some of which may be attributed to the inclusion and digestion of fragments of greenstone, but others may be the result of differentiation of the magma or even to separate intrusions of granitic rocks. The normal or regional type is a grey rock of medium texture, with quartz a rather abundant constituent. Microscopic examination of several samples shows less variation in mineral composition than the field appearance of the rocks would lead one to expect. Near the main shaft the granite is decidedly red in colour and contains considerable pyrite, probably owing to its proximity to the vein. Under the microscope, the constituent minerals are seen to be orthoclase, plagioclase, and quartz, with sericite formed as an alteration product of the feldspar and pyrite, replacing all of the rock-forming minerals. At the west shaft the granite is pale yellowish-green in colour, but an examination shows no difference excepting a somewhat smaller proportion of orthoclase than in the granite from the main shaft. As stated above, the contact is in some places remarkably sharp, but locally there has been assimilation of greenstone by granite, so that the rock, although retaining a granitic texture, is greenish in colour by the development of ferro magnesian minerals. In general, the veins of the Regina are normal to the contact between granite and greenstone, and some of them have been traced across from one rock into the other. They are decidedly lenticular. The largest and most important vein upon which the main shaft was sunk (No. 3 according to Parsons) is now so concealed by workings that it can be seen at only one place on the surface. It outcrops on the side of the hill, two hundred feet S. 600 E. from the shaft. The strike at this point is S E., and the vein seems to be nearly vertical. The width of the quartz is two feet. It is white and somewhat glassy in appearance, but along fracture lines there are slight yellowish stains from decomposed iron minerals. The wall rock on both sides is granite in which there is a great deal of limonite, and evidently the fresh rock contained much pyrite. *--" :;; At the shaft, the vein is in granite, but the strike is transverse to the contact, and southward on the surface it passes into greenstone. The contact plane between the granite and greenstone is said to dip to the north at an angle of 50 0, so that the shaft passes into greenstone between the 4th and 5th levels. The following are descriptions of the main vein as it occurs underground: The vein upon which the shaft was sunk varies in width from about two feet to six feet, with a general average, so far as seen by the writer, of about four feet, and at only one place \vas a width of less than two feet'noted. 1 This applies to the upper four levels. in lower levels as follows: James A. Bow describes the veins The vein in the mine varies in width from about one to nine feet. It is much larger in the lower levels than in the upper. In the 100-foot stope commenced in the fifth level, it averages six feet. It averages about seven feet from start to finish in this level and is nine feet at one place. In the sixth level, it runs from one to five or six feet. 2 A shaft, southeast of the main shaft, may be on the continuation of No. 3 vein. A shear zone striking S. 700 E. in greenstone contains lenses of quartz, 1A. L. Parsons, Ont. Bur. Mines, Vol. XX, pt. l, 1911, p Ont. Bur. Mines, Vol. VII, pt. l, 1897, p. 43.

16 12 one of which has a width of ten inches; other parallel lenses are as much as two inches wide and seven or eight feet in length. Southeast along the strike of this zone, there is a lens of granite, along the southwest edge of which there is an 8-inch lens of quartz. On this, a shallow open pit has been made, but the mass of quartz proved to be shallow as well as short. The main granite contact is about thirty feet north of this shaft. The vein material consists mostly of rather glassy quartz which forms stringers in a rock highly impregnated with pyrite, so that on the dump it weathers reddish brown. Southwest shaft, Regina mine, showing shear zone. Parsons describes two other veins and states that the tunnel east of the buildings was driven on vein No. 6. So far as can be seen at the entrance to the tunnel, the vein is very small. On the hillside above it, a vein two inches wide was noticed, the strike of which would carry it directly to the tunnel. The greenstone-granite contact line swings northward down the hill towards the lake, so that the tunnel entrance is in altered greenstone. West of the main workings, two shafts were sunk. The northerly shows a lens of quartz that has a width of ten inches in the northern face of the shaft

17 13 and does not appear at all in the opposite face. The country rock is granite. The southern shaft is in greenstone on a shear zone three feet in width, the strike being southeast vertical. As in the shaft southeast of the buildings, there are here a number of quartz lenses in rusty-weathering rock. In this case, however, the rusty rock in the shear zone seems to consist to a considerable extent of iron carbonates. The massive fine-grained greenstone of the walls, however, does contain cubes of pyrite and along the vein is very heavily pyritized. Some other veins were noticed which have not been opened up. A vein fifteen inches wide occurs in granite below high-water mark along the west shore of the bay. No continuation of it southward could be found. Only the main vein seems to have given workable ore bodies. It has been stated that the main shoot was chimney-like, and it probably was closely related to the contact between the granite and greenstone. Two samples of ore were taken from material left in the ore bins: No. l consisted only of quartz; No. 2 was made up of pyritized rock. The following assays were made at the Provincial Assay Office, Toronto: No. l No. 2 Gold J2.40 per ton Gold #6.00 per ton W. K. MCNEILL, Assayer. From the descriptions just given, it is clear that on the Regina property there is a series of veins lying partly in greenstone and partly in granite or in one or the other, but always near the contact. It may be expected that the most regular portions of the veins will lie in the granite, as that rock is more homogeneous than is the greenstone, which had already undergone some dynamic metamorphism before the cooling of the granite. The position of ore shoots in the veins is a question that cannot be predicted theoretically, but it seems probable that the highest values will be found in the greenstone directly at the contact. In working veins of this class, it must be borne in mind that the ore shoot will probably have a chimney-like form, controlled by the contact between the granite and greenstone. The vein will probably have local enrichments where it crosses dikes of granite. Rush Bay Locality Golden Horn. The Golden Horn mine is situated on the narrow neck of land separating Rush bay from Echo bay, Lake of the Woods. The shaft is about one-quarter of a mile south of Rush bay. A section across the point shows that the rocks have a linear arrangement parallel to the elongation of the point, and no doubt this part of the lake owes its configuration to the banded arrangement of rock types. No detailed survey of this property was made, but from Rush bay south the following sequence of rocks was noticed: On the point immediately north of the landing, the rock is a very fissile chlorite schist with markings that look like very much squeezed ellipsoids; at the landing there is massive greenstone which shows no ellipsoids, although along the south shore of Rush bay at a point south of the large island and about half a mile east of the mine landing ellipsoids of large size are well developed; south of the greenstone, the consolidated rocks are covered by clay as far as the mine dump. The rock south of the shaft is highly quartzose, reddish on the weathered surface, and a faint yellowish-green on fresh fractures. Under the microscope, it has a spotty appearance as if clastic. Sericite is the

18 14 only identifiable mineral. South of this ridge, the rock is a green schist and farther south a massive greenstone. Along the shore of the sandy bay, on the Echo bay side of the point, there is a grey and green schist with eminent fissility striking east and west and dipping 800 N. On the fresh cleavage faces are elongated elliptical markings, which weather into cigar-shaped depressions. Golden Horn mine, Rush bay, Lake of the Woods. No vein can be seen at the main shaft of the Golden Horn, but at a prospect shaft 200 feet southwest of it there is a quartz vein two and half to four inches in width striking N W. Two hundred feet S E. from the main shaft is an irregular vein trending northerly. The quartz in it is white with practically no metallic minerals associated. Point on Rush bay, Lake of the Woods, north of Golden Horn mine. The main vein is described by W. E. H. Carter as follows: The shaft has been sunk in the chlorite schist on a quartz stringer one foot wide at the top, 2 1A feet at 30 feet depth, and pinching out at 45 feet. On both sides are other irregular small quartz bands. Below the 45-foot level no quartz is to be seen, although in the footwall another band occurs which is followed on the level at the bottom, where its width is l to l ^ feet. 1 iqnt. Bur. Mines, Vol. XI, 1902, p. 252.

19 15 [The vein] is very irregular in width, waving in and out from a mere stringer to a solid quartz body 3^/2 feet wide. The one solid band occasionally-breaks up into several, which then interband with the chlorite schist forming a well-defined deposit several feet wide. 1 Galena, zinc blende, and pyrite are reported to occur in the veins, but the gold values seem to have been low. Some of the quartz on the dump is pure white and some has a bluish shade. Samples of both kinds were assayed with the following result: white quartz gold, Si.60 per ton; blue quartz, 5.80 per ton. Mines near Bald Indian Bay, Andrew Bay and Witch Bay Sultana. The Sultana mine situated on the northwestern part of Sultana island in Bald Indian bay was for many years the leading gold producer of Ontario. It is credited with a production of approximately a million dollars of gold. Operations began in 1891 and continued almost without interruption until The suspension of operations was the result in part of difficulties arising from the granting of underwater rights to another company and the resulting inflow of water from the Crown Reef vein workings, and in part from the supposed faulting of the vein. Much of the later work, for example the Sultana mine, Bald Indian bay, Lake of the Woods. long drift northeast on the 7th level, was undertaken on the assumption that the downward continuation of the Sultana lenses was northwest of the upper work ings. This point will be discussed in connection with the description of the Sultana ore bodies. On Sultana island, a group of old rocks including greenstone sedimentary cherty rocks and quartz porphyries is intruded by a coarse-grained fresh granitic rock that exhibits a great variety of porphyritic textures. A dark-grained, amphibolitic dike is believed to be later still and to intrude the granite as well as the pre-granite rocks. The greenstones occur as a narrow belt, the extreme southwestern tip of which is exposed at the mill. The dark, fine-grained rock that occurs in some quantity on the dump is probably the same variety. Exposures of the green stone occur along the shore north of the landing and as isolated knolls north of the dwelling houses. Eastward, the area of greenstone extends to the bottom of the bay behind the houses, and the contact between it and the granite then swings southward to the southern end of the island. Under the microscope, a sample from the outcrop at the mill shows a finelont. Bur. Mines, Vol. XIII, pt. l, 1904, p. 61.

20 16 grained aggregate composed chiefly of small crystals of light-green amphibole. A specimen from one of the exposures north of the dwellings is made up of a felt of tiny plagioclase laths with sheaf-like bundles of amphibole. A few areas of quartz seem to be secondary in nature. This rock is an altered lava somewhat less basic than the one just described. The contact between granitic rocks and greenstone is fairly sharp, notwith standing the fact that the plane of contact is in many places not steeply inclined. This is well shown on top of the hill northeast of the shaft, where patches of greenstone rest on the granite with a nearly horizontal contact plane. Dikes of granite, of course, radiate off into the older rock, but there is no broad hybrid zone. The cherty sediments shown on the map are well-banded rocks consisting almost entirely of grey to greenish fine-grained silica. They have exactly the appearance of the cherty layers in iron formation, but ferruginous bands are lacking. There are no other types of sediments associated with them, and the contact between the cherts and the greenstone to the north shows no evidence whatever of any break. The southern contact is not exposed. It is likely that they were formed from silica-saturated seas or lakes during an interval in the volcanic activity. The quartz porphyry along the northwestern side of Sultana island and on the island to the north is a greyish-weathering rock that on the fresh fracture is very dark grey to nearly black. In places, the small clear eyes of quartz are very abundant, but in other specimens they are sparsely distributed. A thin section of a specimen from the island north of Sultana island shows a decidedly porphyritic rock with rounded phenocrysts of quartz and blocky, well-formed crystals of orthoclase. Most of the quartz crystals are oval, but a few show embayed outlines. The groundmass is fine grained and has a well marked flow structure which curves around the quartz and feldspar phenocrysts. Quartz porphyry is in contact with greenstone at the northwestern point of Sultana island, but the two rocks at that place are so similar in appearance that their relation could not be satisfactorily determined. This is in part due to shearing and alteration and in part to an apparent transition from quartz porphyry with abundant glassy quartz phenocrysts to those with little free quartz and finally to rocks of greenstone type without visible quartz. The determination of the origin of the quartz porphyry rests upon this relationship, and although no definite proof excepting the microscopic evidence can be cited, it seems likely that the porphyry is a flow rock belonging to the same general period of volcanic activity as does the greenstone. The granitic rocks of Sultana island have a remarkable zonal distribution which can be best appreciated by reference to the map. The marginal type is a dark-grey basic granite that contains dark-coloured patches that may either be segregations or almost completely digested inclusions. The microscope shows rocks of this type to consist of quartz orthoclase and plagioclase with sericite as an alteration product. The basic segregations are almost colourless, nonpleochroic hornblende, with some alteration to chlorite. The groundmass of the porphyritic granite is very similar to the massive granite. The phenocrysts are white to bluish or lavender-coloured feldspars. Along certain zones crushing has folded the dark-coloured constituents around the phenocrysts, producing an "augen" texture. The phenocrysts are found to be microperthitic in character and considerably sericitized. The abundant quartz shows strain shadows. The dark mineral in this rock is biotite, which is

21

22 18 width sixty-six feet of nearly solid quartz, twenty feet of which, however, was said to be low-grade; 4th level, ninety-four feet south of the shaft, width thirty-two feet and footwall not exposed. Below the 4th level, the mine plans show that the quartz body contracted considerably, and at the roof of the 7th level the lens became so small that those in charge at the time came to the conclusion that the vein had been dis placed by a low-angle fault. It was believed that the fault plane had a northeastsouthwest strike and a dip of 66 0 S.W. The outcrop was supposed to be along the drift-filled valley that comes down to the bay north of the shaft. 1 No evidence of such a fault has set out in any descriptions of the mine, and it seems likely that it was assumed as a way of explaining the non-appearance on the 7th level of the huge mass of quartz of the 2nd, 3rd, and 4th levels. No indication of any fault line was found on the surface in the position stated; furthermore, the band of siliceous sediments crossing the bay shows no displace ment, as would have been the case except under very special relations of the fault plane. The top part of the vein was assumed to have moved downward and westward, and the 7th level was driven northeastward to intersect the con tinuation of the vein beneath the fault plane. If the contact between granite and greenstone is vertical or steeply inclined, then any motion such as assumed would place the contact between these two rocks farther to the east beneath the fault plane, than it is above the fault. In the mine plans, the contact is indicated where it is crossed by the 7th level. Instead of occurring far to the northeastward as the fault hypothesis would require, it is actually about fifty feet southwest of its position on the surface. Neither of these facts is absolutely conclusive, but the statement has been made that the vein actually does continue in its regular position below the 7th level, and it is probable that the loss of the vein was merely the contraction of the quartz lens, as commonly happens in all veins in these ancient rocks. This mistaken interpretation of the geology led to a considerable waste of money, so that there seems to have been no thorough exploration downward to see whether or not other lenses occur in depth. The Crown Reef vein is transverse to the main vein system. The vein dips northward and is somewhat irregular in trend. It has been stoped up to the surface, and the underground workings on it are connected with the main Sultana shaft. The main vein is stated by Coleman 2 to be in altered trap, but if so it must lie very close to the contact with the granite and in depth probably passes into it. The Galena and Bullfrog veins are wholly in the granite or granite porphyry and seem to lie close to the contact between those two rocks. The Crown Reef vein lies entirely in granite porphyry. Other veins occurring southeast of the shaft lie near the contact between granite porphyry and massive granite. This association is so close and so constant that a genetic relationship seems likely. It is possible that the contact zone between the two rocks was a line of weakness along which strains, developed during the cooling of the igneous mass, were relieved, and the fractures so formed offered easy access to the ore-bearing solutions. 3 The Sultana produced an important amount of gold, and there was apparently a profit during a large part of the time it was operating. The ore body was lenticular, as might be expected, and it seems likely that it contracted!qnt. Bur. Mines, Vol. XI, 1902, p Ibid, Vol. IV, 1894, p The writer is indebted to J. G. Cross for suggestions concerning the granite porphyry.

23

24 20 scope, is found to contain abundant biotite, some quartz, considerable calcite, and some tiny prismatic crystals of blue tourmaline. No rock of this kind outcrops in the vicinity, and it is probably a facies of the vein rilling. Most of the quartz in the vein is white, but some specimens show a faint rose tint. Where it cuts the biotite schist, the colour is a faint blue, and pockets of siderite are common. Few metallic minerals are present in the quartz, but the biotite rock contains abundant cubes of pyrite, which reach a diameter of one-fifth of an inch. Assays of quartz from the dump have been reported to be high. No native gold was seen, and care was taken to secure a sample that contained none. An assay at the Provincial Assay Office gave a value of S42.60 in gold. All reports agree in the high gold values contained in the quartz from this claim. The difficulty seems to have been that the lens was small. Here, as at the Sultana, thorough prospecting may discover other lenses of quartz lying along the same fissure. Wendigo. The Wendigo mine is situated a half mile north of Witch bay. The country rock is a greenstone somewhat schistose near the vein, but fairly massive south of it. The main vein is parallel to the schistosity. One hundred and fifty feet east of the shaft, the vein has a width of quartz of 2^ feet in rusty schist. Pyrite, pyrrhotite, and chalcopyrite are fairly abundant, and gold was seen in one sample from the dump. One hundred and fifty feet west from the main shaft, a shaft has been sunk on a zone of sulphides, which has a width of six feet with some quartz stringers. Here and at the main dump, some large masses of solid sulphide occur, but an assay gave only S 1.20 in gold. One hundred and fifty feet north of the main vein is a small parallel sulphide zone in massive altered greenstone. The physical appearance of the Wendigo vein is exceptionally promising, but in view of the low assay from solid sulphide vein material, it is doubtful if there is any possibility of finding a workable deposit. Gauthier Claims. A number of claims on the north side of Andrew bay have been rather thoroughly prospected and some interesting veins uncovered. The rocks consist of rather schistose greenstone intruded by acidic rock. Under the microscope, the latter is found to be a typical granite made up of quartz, orthoclase, and acidic plagioclase, with sericite plentifully developed. No dark minerals are present. Considerable work has been done on a small, but rather persistent, east-west vein of quartz, occurring in a sheared zone four to six feet wide in granite. The width of quartz is two to three inches, and large pellets of gold occur commonly, filling spaces between needles of actinolite. There is no apparent alteration of the wall rock, and the vein is too small to be workable alone. A larger vein near the lake shore on the south side of the group of claims, with a strike north west-southeast and dip 600 N.E., has a width of six feet of blue and white quartz, in which there is considerable chalcopyrite, some galena, and a little arsenopyrite. The country rock is chlorite schist. The vein has not been stripped and can be seen only where a pit about eight feet deep has been sunk on it. Samples of both types of quartz were taken, which gave the following results: Blue quartz gold per ton White quartz gold Si.00 per ton Other shear zones in the granite with widths of one to twelve feet, contain veins of quartz with pockets of galena, pyrite, and chalcopyrite, varying from fractions of an inch up to two to three inches in diameter. Shear zones are

25 21 separated by twenty-five feet or more of unsheared granite. Assays of solid galena give good values in silver, and pyrite associated with the galena carries as much as 2.00 per ton in gold, but the quantity of the sulphides is too small to be workable. Dorions Island. On an island lying about two miles west of Yellow Girl point, two shafts, one vertical, the other one hundred and fifty feet from it, but inclined at an angle of 40 0 towards the vertical shaft, have been sunk on a fractured zone eight to ten feet in width striking northwest-southeast and dipping 800 S. The inclined shaft has a depth of thirty feet on the incline. The fractured zone shows some silicification and serpentinization, and there are small veins of quartz and iron carbonate. Assays give negative results. Mines East of Kenora At various times properties lying in the district along the railway, eight to ten miles east of Kenora, have been worked. Extensive development work was done at the Scramble mine, Black Sturgeon, and others as early as 1894, and again on the Scramble between 1911 and Visits were made to some of these during the present examination, but no detailed mapping was under taken. Champion. The most aggressive work at present being done is on a group of claims known as the Champion mine, which is situated a half mile south of the station Margach. During a previous period of development, a shaft was sunk on the property and an adit driven from the valley into the side of the hill below the tunnel, connecting with it at a depth of about thirty feet. During 1924, a power plant consisting of two 50 h.p. boilers, a six-drill compressor, and a hoist has been installed. The work is under the general direction of Charles Brent. It is proposed to retimber the shaft and proceed with under ground development. Water for the camps, which are situated in the valley near the tunnel entrance, is to be brought by gravity from a lake lying behind the camps. At the time the mine was visited, work was directed chiefly to this undertaking. The camp and the power plant are situated in a narrow valley trending southeast. On the northeastern ridge, the rocks are extremely heterogeneous, varying from a basic speckled black and white granite or granodiorite to fine grained black amphibolite. Dikes of light-coloured normal granite and felsite occur. The southwestern ridge consists chiefly of a dark-coloured biotite granite, somewhat variable in the amount of dark constituents present. At the base of the ridge near the adit, the rock is granodiorite. Westward along the road over the ridge, it is fine-grained amphibolite with no feldspar at all recognizable. Still farther west are grey-weathering granitic rocks consisting of hornblende and pinkish feldspars. Dikes and irregular masses of light-pink granite intrude the complex. The shaft is sunk in an irregular elliptical mass of the light-pink granite on the southwest ridge. The length of the lens is about one hundred feet and the maximum width twenty-five feet, the longer axis being parallel to the ridge. At the northeastern end it divides into smaller dikes which taper out sharply. In the pink granite irregular veins of fine-grained white to pinkish quartz have widths varying from a foot to eighteen inches. Another dike of pink granite fifteen feet in width occurs at the mouth of the adit. Much of the intrusive is massive and fresh, but in certain zones there has been some shearing so that

26 22 the rock is foliated. Gold can be panned from the intrusive granite, especially where it is sheared, and a sample of quartz from the dump gave an assay value of S15.20 in gold, none of which was visible in any of the samples chosen. The quartz veins are too few, too small, and too irregular to be workable alone, and the possibilities of the property as a gold producer depends upon whatever average gold content any large part of the granite lens may be found to carry. Hilly Lake. Hilly Lake mine is situated on the west shore of Hilly lake. Only a little surface work is being done on the property on which an open-cut, 100 feet long and ten to twelve feet deep, and some surface trenching is the extent of the development. There is a small mill on the property. The vein upon which the open-cut has been made extends from the lake shore southwest and dips 70 0 S. A shear zone thirty inches wide in granite contains a quartz vein three to four inches wide on the footwall. The quartz is fine grained, bluish to pinkish in colour, but with dark streaks, in which some spectacular specimens of gold occur. Pyrite is disseminated through the wall rock. A second shear zone occurs in a grey granodiorite, north of the dwelling about 400 feet from the one just described and parallel to it. A few quartz stringers traverse the sheared rock and pyrite is found even in the massive granodiorite. The zone has been stripped for a length of 250 feet, and two test pits eight to ten feet deep have been sunk. The high-grade vein showing in the open-cut is too narrow to be workable in spite of the many occurrences of visible gold in it. The other shear zone contains only a small amount either of quartz or of metallic minerals. Rainy Lake Area The Geological Succession at Bears Pass The geology of the Rainy Lake basin has been a matter of controversy since the original report of Lawson, and different opinions are still held by many who have studied the rocks of that region. Lawson's original classification 1 was somewhat revised in a later report, Geological Survey of Canada, Memoir No. 40, which embodied the results of a re-examination and corrected some errors such as would be expected to occur in work done under the conditions of the original survey. The revised classification is as follows:- Algoma granitic gneisses, etc. Lamprophyres Intrusive contact Seine series Uniformity Laurentian granite gneisses, etc. Intrusive contact Keewatin Coutchiching Some important features of this classification have been widely adopted in describing pre-cambrian successions in various parts of Ontario. The relations of the lower formations, the Keewatin and Coutchiching, have not, however, received unanimous acceptance, and some authorities hold that the Coutchiching is merely a local facies of the great Keewatin complex. Several days were spent in mapping in considerable detail the area from Bears Pass station westward to Bears Passage, an area which is convenient and which igeol. Surv. Can., Vol. Ill, pt. F,

27 23 gave a good type section of the rocks described by Lawson. During this time the writer had the co-operation of J. W. Greig of the Geophysical Laboratory, Washington. The Coutchiching rocks are well exposed along the Canadian National railway from Bears Pass station westward to the crossing of Bears Passage and also along the lake shore from a point north of the station westward across the strike of the rocks to the northern end of the Passage. The common type is a greyish granular rock which weathers brown. The texture varies somewhat, but in most samples the chief minerals, quartz, feldspar, and biotite, are recogniz able in the hand specimen. In some beds, secondary porphyritic constituents such as garnet or staurolite are abundant. The garnets are light-pink in colour and commonly rounded; the staurolite occurs in dark-red, well-formed crystals which may make up a large part of the rock mass. Usually it is confined to certain beds, probably originally somewhat clayey. Stratification is clearly Coutchiching sediments along the axis of the Bears Pass anticline. marked by colour banding and by variations in grain or in the kinds of minerals. The upper beds are more massive than the lower, and staurolite is more abundant in them. There can be no doubt whatever that the whole series was originally an impure sandstone with some beds which contained a considerable quantity of clay. The structure is shown by the dips recorded on the map and section. The Coutchiching rocks form an anticline, the axis of which strikes northeast-south west and appaiently plunges northeastward, but with cross-folds which in places reverse the plunge of the axis. On the limbs of the fold, the sedimentary beds strike northeast-southwest. Along the axis of the anticline, the strike is north west-southeast, where the beds swing round the nose of the plunging fold. This can be well seen in the rock cuts a mile east of the bridge where rather massive beds exhibit gentle minor anticlines and synclines parallel in strike and plunge to the major structure. The beds along the axis are also well exposed on the lake shore directly north of this point. In short distances outward from the axis in both directions, the dip of the beds increases to comparatively steep angles, and near the contact with the

28 24 Keewatin rocks dips as high as 600 were noted; in all cases, however, these were towards the contact. The thickness estimated from observed dips along a northwest-southeast section is approximately five thousand feet, with the base still unexposed. The Keewatin consists of dark-green chloritic rocks, massive or schistose. The texture of many of them is fine-grained, and the constituent minerals are fibrous amphibole, chlorite, and some quartz. Other varieties have a coarser texture with larger and somewhat blocky crystals of amphibole, which may have been derived from the alteration of original pyroxene. On Lawson's map, a distinction is made between these two types, the finer grained variety lying next the Coutchiching. The fine-grained greenstone is similar in all respects to greenstones in other areas, which exhibit ellipsoidal structures and which are therefore considered to be lava flows. It is difficult to draw exactly the boundary line between Keewatin and Coutchiching rocks. Drift-covered contacts are the rule, and in addition the sediments become chloritic and massive near the contact, so that there is no sharp change to the chloritic rocks grouped with the volcanics. Lawson states that there are interbandings of the two, but this statement may rest upon the evidence of the contacts near Bears Pass station, where bands of dark-green rocks alternate with Coutchiching sediments. The relation there, however, is probably an intrusion of basic sills along the bedding. In one of these, at least, both margins show considerably finer texture than does the middle of the band. Stratigraphically, there is no evidence of any interval between the two rock series, and the contacts give no evidence of the order of superposition. Struc turally, however, there seems no doubt that the Coutchiching sediments of this section lie beneath the Keewatin greenstones. Intrusives of various types cut the Keewatin and Coutchiching. A some what variable rock, which in places is very dark coloured, has been classed by Lawson as mica syenite. The main igneous intrusive is the granite, to which the name Algoman is applied. It truncates the Coutchiching and Keewatin rocks east of Bears Pass. Another isolated mass of granite not shown on Lawson's map occurs near mile post 66. Only one occurrence of rock of post-algoman age was observed in this vicinity. A narrow basic dike cuts the granite of the boss at mile 66. Whether this should be classed as Keweenawan or as one of the lamprophyres is doubtful. If the latter, then the lamprophyric rocks are post-algoman, rather than pre- Algoman. Other features of the geological section will be dealt with in the detailed descriptions of some of the mining locations. EAST SHOAL LAKE MINES General Geology The area in which East Shoal and Bad Vermilion lakes are located is underlain by rocks of Lawson's Keewatin, Laurentian, and Seine group. The Keewatin does not differ in general appearance from the Keewatin of the Bears Pass section; local peculiarities will be noted in the detailed descrip tions. The Keewatin rocks are intruded by a great granite batholith that Lawson considers to be older than the Algoman granite of the Bears Passage section. The chief facts upon which he bases his opinion are the unconformable relationship of the Seine conglomerate upon the East Shoal lake granite and the intrusive relationship of another granite to the Seine conglomerate farther

29 25 east. Microscopic examination of granite from Bears Pass and of granite from the Foley mine on the north shore of East Shoal lake, shows some differ ences that may be significant. The former consists of microcline orthoclase, quartz, high soda plagioclase, muscovite, and some chlorite. It is remarkably fresh and unaltered. The latter, even in samples from drill holes not in the vicinity of veins, shows a considerable degree of sericitization of the feldspars. Microcline is not abundant, but this slight variation in mineral composition is of little significance. Since it is certain that there are at least two periods of granite intrusion and since there is some difference in degree of metamorphism in these two areas, it may be assumed, unless further evidence is found, that the granite of East Shoal lake is pre-seine in age while the Bears Pass granite is post-seine. Parsons has expressed the opinion that the granite at Bad Vermilion lake intrudes the Seine conglomerate, 1 but its pre-seine age is very clearly shown along the contacts near the Foley mine where the conglomerate rests directly on the granite with gentle dips away from it and where the basal beds include fragments of the underlying granite. In places, the matrix of the sediment can be seen filling in beneath latge boulders, which still lie practically in their original places on the granite floor. The lamprophyric rock, which is well exposed at the Foley mine, intrudes the conglomerate. In the hand specimen, the lamprophyre is a dense black rock weathering to a rough, pitted surface. The microscope shows the rock to be decidedly porphyritic with large blocky crystals of plagioclase of medium character. The fairly fine grained groundmass consists of a large proportion of biotite. Fragments of conglomerate are included in the lamprophyre, which has absorbed the matrix leaving the pebbles practically unattacked. A small outcrop lying directly north of the Foley mine shows this effect remarkably well. Mines of East Shoal Lake Area Gold was discovered in the Mine Centre area in 1893, and during the years up to 1900 there was much activity. The total production of gold is said to have been approximately a quarter of a million dollars, of which the Foley produced 175,000 and the Golden Star, 161,000. Foley. The locations later known as the Foley mine (A. L. 74, 75, 76) were discovered by Thomas Weigand and Alexander Lockhart in September, Development work and mining were carried on until May, 1898, and in 1900 work was begun in March and continued until December. After that time nothing was done with the property until 1920, when an option on it was taken by the Swedish Mining Syndicate and the workings were partially dewatered and sampled. In 1922, the property was taken over by the British Canadian Mines, Limited, by which company it is at present being actively developed. During 1924, underground work was being done from both the north and south shafts, and a diamond-drilling campaign was begun during the winter of The rocks in the vicinity of the Foley workings have been described pre viously. The known veins occur only in the granite. As will be seen from the map, they fall into two groups: a parallel series striking almost due north; and another series roughly parallel, but somewhat more irregular, striking slightly. Bur. Mines, Vol. XXVII, pt. l, 1918, p Geol. Surv. Minnesota, Vol. 23, p. 81.

30 26 west of north. Both sets of veins are remarkably persistent. The Bonanza vein upon which the north shaft is sunk is one of the north-south series. On the 150-foot level, it has been followed 150 feet south. The width averages two feet for most of this distance, but at the southern face of the drift it pinches to a mere stringer. On the 200-foot level, the Bonanza vein has a width of twenty-six to forty inches. It has been drifted on for a length of 100 feet north, and this part of the vein has been stoped from the 3rd level up to the 150-foot level. South of the shaft the vein carries a good width for eighty feet to a point where there is a plexus of cross veins. Beyond that, the vein has been traced for twenty feet, but is narrow. A raise at the point where the cross veins occur shows the main vein widening to eight inches. On the 300-foot level, a drift south from the shaft 150 feet in length shows the width of the vein to be from three inches to thirty inches. Northward in a drift forty feet in length the maximum width is twenty inches. Between the 3rd and 2nd levels, the average width is thirty inches. On the 400-foot level, the Bonanza vein has been followed 200 feet to a split in the vein. One branch bends 25 0 to the east and has been followed another two hundred feet. The other branch dies out in a distance of thirty feet. From the shaft to the dividing point, the width of the vein is from one foot to forty inches. Beyond the flexure the vein is narrower, and at the face has a width of three inches of quartz. The average dip of the Bonanza vein is 75 0 to 80 0 to the east. The quartz is rather glassy, but has a ribboned structure with dark bands paralleling the wall of the vein. Pyrite, galena, and sphalerite are present in small amounts. The wall rock is granite along the whole vein as at present developed. It looks very fresh, but a sample from the wall of the vein on the 400-foot level shows that the feldspars are considerably more altered than are those in rock not in proximity to veins. Dark minerals are not abundant in any samples of the granite, and most of them are altered to limonite, which forms a faint stain. In many specimens pyrite occurs as an introduced mineral. On the 400-foot level, a crosscut west 190 feet encounters a vein known as the Jumbo. It dips 75 0 to 80 0 E., as the Bonanza does, but seems to be one of the system striking northwesterly. Its width is twenty-six inches to thirty inches on this level. On the 150-foot level, the crosscut starts from a point 150 feet south of the shaft, and the distance westward to the Jumbo vein is 110 feet. The dip at that point is 85 0 E., and the width four to five feet of white to pinkish quartz containing a little pyrite. On the surface, a vein known as the "A" vein lies 100 feet east of the Bonanza and parallel to it. The width is twenty inches to two feet, and the quartz carries some pyrite. This vein has been reached by crosscuts on the 400-foot level, and samples of the wall rock, which is also granite, show considerably more alteration than any other samples examined. There is also a sparing replace ment of the rock-forming minerals by pyrite. The "sulphide" vein, also lying east of the Bonanza, has a shallow shaft sunk on it. At the surface, the width is forty inches, and down the shaft it widens to five feet. This vein contains a considerably larger proportion of sulphides in the quartz than do the other veins. The metallic minerals are sphalerite, pyrite, galena, and chalcopyrite. The quartz is decidedly reddish in places. On the 60-foot level of the south shaft, a vein of ribboned quartz, which attains in places a width of two feet has been followed seventy-five feet north and sixty feet south of the shaft. This is thought to be the Bonanza vein, and high values are reported at some points in it. On the 200-foot level, the vein is

31 27 fifteen feet east of the shaft and one and a half feet wide. One hundred and fifteen feet farther east is a strong vein with a width of six feet of quartz with well-marked ribbon structure. The dip varies from vertical to 85 0 E., and the strike 100 west of north. This vein has been christened the "Daisy," but may possibly be the Jumbo vein of the north shaft. If so, there is an intersection with the Bonanza vein. The "Lucky Joe" vein is one hundred and ninety-five feet east of the Daisy, to which it is parallel, but with a dip of 800 W. The quartz is fourteen inches in width and milky in colour. Other veins are shown on the map, one of which, the west vein, is remarkable for its regularity and continuity. Some of these veins have been stripped in places, but the greater part of the work has been confined to those described above. High values have been obtained from some samples, but the gold content is exceedingly variable. The lack of any extensive mineralization of the wall rocks leaves only the quartz as possible ore. Hence, with the widths detailed above, it will be necessary to have high values in the veins proper to make mining profitable. Owing to the variability of values, assay results are unreliable, and only mill tests on considerable quantities of quartz will give accurate data as to the return that may be expected. The production of gold from the Foley as reported to the Ontario Depart ment of Mines was as follows: Year Tonnage milled 4, Value bullion #32,928 6,297 Stagee Claims. Claims held by G. Stagee lie in the northeastern corner of the block, of which the Foley holdings form the other three-quarters. The geological relationships are similar, excepting that no lamprophyre occurs. The veins exposed belong to the northwest-trending system, and some of them have been traced continuously from the Stagee claims on to the Foley; they are similar in character on both properties. Considerable work has been done in the way of stripping and in sinking test pits. Gold can be seen in the veins at a number of places. Golden Star. The Golden Star mine, situated between the Foley and Bad Vermilion lake, was the largest producer of gold of the area. Veins were discovered on this property in August, 1894, and some development work was done by the original owners before it was turned over to the Golden Star Mining and Development Company in March, Work by this company was begun almost immediately and was carried on practically continuously until Further development was done in 1901, and a total of about S30,000 was expended; but the mine was again closed, and nothing has been done in recent years. Little can be added to information already published concerning the mine. What seems to have been a very thorough examination was made by James A. Bow, 1 and his report indicates that the ore bodies were of sufficient grade and size to be workable under present conditions. The geological relationships are shown on the accompanying map, and Lawson's interpretation of the sequence of events seems to be correct. For the most part, the Keewatin rocks consist of greenstones, some of which are schistose to varying degrees, while others fracture into angular blocks along incipient joint planes. The texture varies considerably, but most of the rocks are fine-grained; a few have ellipsoidal structure. There is some variation iqnt. Bur. Mines, Vol. VIII, pt. 2, 1899, pp

32 28 in composition, and a type that is apple-green in colour contains quartz phenocrysts. All facies, however, are grouped together in mapping, as they seem to belong to one great period of volcanic effusion. The granite which intrudes the greenstone is similar in all respects to that described previously at the Foley. The contact with the greenstone is remark ably sharp, with few dikes of granite in the greenstone, and there are neither fragments of greenstone in the granite nor any development of hybrid rocks or gneissic marginal zones. Near the conglomerate, the granite shows more alteration than farther away, and weathering has produced ridges and hollows in it. This is apparently the result of surface alteration previous to the deposition of the Seine series, and has been noted by Lawson. The basal beds of the Seine series are coarse greywackes, which contain considerable quartz, interstratified with beds containing many pebbles. The higher beds are conglomerate, in the lower part of which angular fragments are set in a matrix of greywacke and in the upper part in a chloritic base. The ore bodies are related to the intrusion of the greenstone by the granite and its accompanying dikes. The vein contains a large amount of siderite, which is cut by quartz lenses. Apparently the first stage in the intrusion was the alteration of zones in the greenstone to siderite, and this was followed by fracturing and the introduction of the gold-bearing quartz. A sample from the vein 100 feet south of the shaft across a width of seven feet, gave no values in gold or silver. The sampling by Mr. Bow shows S10.60 across three and half feet. This value, however, may have been confined to certain shoots. Olive. The Olive mine is situated on the south shore of Little Turtle lake, five miles west of Mine Centre station on the Canadian National railway. Light-coloured, well-banded rocks are interlayered with massive green stones, and both are intruded by granite, which forms the islands in Little Turtle lake. Greenstone lies on either side of the light-coloured band in which the vein occurs. The rock to the south of it is coarse-textured and massive, and weathers to a dark-green nodular surface. The rock of the northern greenstone area is slightly schistose and has some variation of colour in light and dark green irregular streaks that may represent distorted ellipsoids. At the eastern end the rock is less schistose and similar to that of the southern area. By microscopic examination, the mineral constituents are found to be actinolite in fibrous and frayed-out bundles, calcite, quartz, some muddy alteration products, and pyrite, which replaces other minerals and has been introduced subsequent to much of the alteration. The light-coloured rocks associated with the greenstone outcrop in three elongated areas. The southern one appears only as small oval knolls in the drift-covered area north of the railway. The second is the band in which the main veins lie, and the third occurs as isolated outcrops in the drift-covered area around the mine buildings and as a fairly continuous outcrop along the lake shore. The rock of the central band is greenish-grey weathering to lighter grey. Laminations are visible on the fresh rock surfaces as colour variations and on the weathered surfaces are remarkably distinct. The number of laminae in places is as many as thirty to an inch. On the northern side of the band, a zone five to ten feet in width is minutely contorted. Schistosity is well developed in the evenly laminated parts and is exactly parallel to the colour banding. Along the lake, the lamination is less perfect and there are many dark-coloured layers among the grey ones. Under the microscope, a specimen of well-banded rock from the shore of the lake is found to consist of a mosaic

33 29 of quartz with interstitial calcite. A few shreds of biotite and a little chlorite are present. The rock is a calcareous quartzite, probably formed during periods of ordinary sedimentation between volcanic effusions. The granite intrudes the volcanic rocks near the lake, outcrops along the north shore, and forms a large part of the two islands lying in the bay. Along the south shore, granite sills are numerous and make up quite a large part of the rock mass. The sediments have been very intimately penetrated by lit par lit injection without much disturbance. In places the stringers of granitic material have pink feldspars, in others the colour is white. On the islands, probably two-thirds of the rock is gneiss, which contains streaks and blocks of partially Quartzite, Olive mine. digested sericitized sediments. Movement during intrusion is shown by dragfolding of the schlieren and rotation of included blocks. A vein upon which two shafts were sunk lies in sediments parallel to the bed ding, N. 800 E., dip 700 N. At the collar of the western shaft, the width of quartz is two and half inches, and eight feet down it is eight inches. Farther down, it narrows again to a mere stringer. Eastward, the vein narrows and swells from a stringer up to a width of ten or twelve inches. The quartz is a finegrained glassy variety, and sulphides are not abundant either in the quartz or in the wall rock! This mine was working in 1898, and Coleman reports that 109 tons of ore from one of the shafts on the property gave an average value of S44 per ton of gold. 1 He describes the vein as six inches to two feet in width, but consisting of a series of overlapping lenses. iqnt. Bur. Mines, Vol. VII, pt. 2, 1897, p. 128.

34 30 It was found that the vein was too small to be treated by itself, and the mill, which at first consisted only of two stamps, was increased to ten, and later to twenty-five, with the plan of milling the schistose wall rock as well as the vein. Diamond-drilling was undertaken in 1899 to determine the width of the mineralized "felsite schist," and an ore body with a total width of 425 feet was reported. This so-called ore body was apparently the band of light-coloured "felsite schist." The mine was closed in June, Upper Seine River Area A group of mines along the upper part of the Seine river produced gold, beginning about 1894, and some were worked as late as No work of any kind is being done at present. A general discussion of the regional geology will not be undertaken, as the rock relations at the four mines that were mapped in detail, Harold Lake, the Elizabeth, Hammond Reef, and Sawbill, are com paratively simple and involve few of the formations of the complex succession of Steeprock lake. Elizabeth. The Elizabeth mine is situated a quarter of a mile north of Rice lake, which drains into the Seine river from the north four miles below the outlet of Steeprock lake. The stream from Rice lake to the Seine river is too small even for canoe travel; hence transportation to the property would have to be by road. The distance from the Canadian National railway is not great, but the Seine river flows between the mine and the railway. The property was discovered by the Anglo-Canadian Gold Estates, Limited, in 1900, and exploration was done by diamond-drilling after preliminary trenching and sinking of test pits. The information obtained by the drills was sufficiently encouraging to persuade the company to undertake mining operations, and by the first part of 1903, 20,000 tons of ore, which it was believed would average S8 to Si O per ton, were blocked out. During 1902, a 10-stamp mill was installed. In 1912, both mining and milling operations were carried on for part of the year, but all work was discontinued August l, The greenstone at the Elizabeth mine is practically all massive and no ellipsoidal structures were seen. Under the microscope, the rock both of the main greenstone area and of the elongated inclusions occurring in the granite north of the workings is found to consist chiefly of needles of actinolite and secondary quartz. The development of actinolite is evidence of the contact action of the granite. None of the inclusions is over thirty feet in width, and they are probably roof pendants not completely absorbed by the intrusion. At the centre of the bands, the rock is massive, the margins are schistose, and in the granite near the contact there are networks of quartz stringers. The granite is rather variable in texture and colour, but some of the varia tions may be due to different degrees of alteration. A sample taken three hundred feet from the contact with greenstone is decidedly pink in colour, and under the microscope is found to contain quartz, microcline, orthoclase, and plagioclase, with some secondary minerals formed by their alteration, but practically no dark-coloured minerals whatever. Near the vein, the rock is considerably altered, and the colour is greenish-grey. Under the microscope, it shows a foliated texture with veinlets of introduced quartz. The quartz of the original rock is still recognizable, but the feldspars have entirely altered to sericite. Some chlorite is present. Dark-coloured dikes cut the granite and no doubt also occur in the area of greenstone, where they would be less easy to distinguish on account of their

35 31 similarity to it. Some of the larger dark dikes are shown on the map. The rock is greenish-black in the hand specimen. Under the microscope it is found to consist chiefly of biotite, which is partially altered to chlorite, considerable calcite, and some quartz. They may have been vogesites originally. The vein upon which the shaft was sunk is not now visible, but the granitegreenstone contact passes directly under the shaft-house, and presumably the vein must have been practically on the contact. Most of the rock on the dump is granite. West of the shaft, a vein lying along the contact has been stripped and in places opened up by pits. The width varies from a few inches up to eight feet. Another vein lies in granite along the west side of the drift-filled valley north of the road. It is rather irregular, but in places attains a width of twelve feet. The wall rock exposed is granite, but this vein probably also lies along or close to the contact. Near the vein, the granite has been altered to a greenish rock cut by a network of tiny stringers. The quartz of the vein is sugary and almost barren of sulphides excepting a very small amount of pyrite. Lenses of quartz are separated by irregular, banded masses of rusty-weathering rock, which contains considerable siderite; similar material occurs on the dump at the main shaft and there, too, sulphides are almost entirely lacking. Some irregular masses of quartz occur in the granite. The following are excerpts from previous descriptions of the veins: The vein is four to five feet wide, strike north and south along the contact between green stone on the east and squeezed granite on the west. 1 The vein under development... lies along a contact between a greyish-green, more or less schistose diorite on the east side and a pink to grey protogine on the west, the contact striking roughly north and south.... The quartz vein either traverses the true contact or more frequently lies wholly in trap or in protogine, removed a few feet from the contact and in nearly every case with smooth walls without selvage, its characteristics being those of a bedded vein of a width varying from one to fourteen feet by gradual lenticular enlargement. In the places where the size has decreased other parallel bands appear, thus maintaining a good width of quartz throughout the mine. 2 Harold Lake. The Harold Lake mine is situated close to the shore at the western extremity of Harold lake. During 1895 and 1896, a 5-stamp mill was in operation, but no work has been done on the property since that time. The rocks in the vicinity of the mine are greenstone, which is intruded by granite, and cutting this a schistose dark-coloured dike was observed. The relationships are similar to those at the Elizabeth. Most of the greenstone is quite massive, but near the contact with the granite, schistosity has developed parallel to the contact, which here is nearly east and west. The granite is similar to that on the Elizabeth and shows an even greater degree of alteration near the veins. The veins seen are all in granite. On one vein, there is an open-cut or a stope broken through to the surface. The northern forty feet of this is com pletely filled with loose rock. The next sixty feet is open to depths up to thirty feet with a width from thirty inches to six feet. At the south end of this section, the vein is exposed with a width of twelve to twenty-four inches of quartz with a band of sheared granite on either side varying from four inches to a foot. Beyond this, the altered granite contains a network of quartz veinlets. The quartz in the vein is coarser in texture than that at the Elizabeth, carries a little pyrite, and has small ramifying cavities which seem originally to have!e. T. Corkill, Ont. Bur. Mines, Vol. XXIV, pt. l, 1915, p W. E. H. Carter, Ont. Bur. Mines, Vol. XI, 1902, p. 241.

36 32 contained siderite. From the south end of the open-cut, the vein turns east parallel to the granite-greenstone contact, but still in the granite. It has been trenched for some distance east, but this part of it is narrow. Near the lake shore a shaft has been sunk on a vein not now visible, but which probably is indicated by a trench extending N W. The material on the dump is nearly all quartz, which contains considerable siderite and some pyrite and chalcopyrite. Masses of chlorite indicate the presence in the vein of altered wall rock. Sawbill and Hammond Reef. The Sawbill and Hammond Reef mines are situated near the southeast shore of Sawbill lake, well towards its northeastern end. This lake is an expansion of the Seine river and may be reached from the railway at Steeprock lake. A winter road has been cut from Sawbill mine to the railway at Hematite. During the period when the mines were working, a stage line ran three days a week from Bonheur on the Canadian Pacific railway to Sawbill lake, a distance of thirty-three miles. On the Sawbill property, a 10-stamp mill was installed and began operations in October, 1897, but the mine was closed down from March until August, 1898, and finally ceased all operations in the autumn of 1899, the workings having reached a depth of 275 feet. On the Hammond Reef, a 10-stamp mill was installed in 1897, and an additional thirty stamps were added and a hydroelectrical power plant built. Operations with the new plant began August l, 1900, but on October 6 the mill motor was burnt out during a thunder-storm; as the results obtained from the deposit were discouraging, all work was dis continued. Much of the machinery has now been hauled out to the railway and lies discarded at the siding at Hematite. A large amount of work was done at this location. The open-cut south of the crusher has a maximum depth of thirty-five feet; near the west end of it is a shaft sixty feet deeper. The geology of the Hammond Reef and Sawbill mines is very simple. The rock is granite with a few small dikes of dark-coloured rock. The granite is fairly fresh and much of it is high in quartz with a very little dark-coloured mineral. Other varieties have a considerable amount of biotite. In some places, there are what appear to be segregations of more basic, dark-grey granitic rocks. Other areas of this kind may be almost completely digested inclusions of greenstone. Some of these are large enough to be shown on the accompanying map. Large zones of alteration occur in the granite. An altered biotitic variety consists of quartz, plagioclase almost completely changed to sericite, and biotite, which is quite green and in part completely chloritized. Any orthoclase that may have been present is no longer recognizable. A pinkish variety of granite consists of quartz, acidic plagioclase, sericite, and a little magnetite. The dark-coloured dikes weather to rusty surfaces. A sample from one near the Sawbill mill is found under the microscope to consist chiefly of chlorite, calcite, and iron oxide. These dikes are later than the granite, and one in open pit No. 2 cuts the quartz veins and so is decidedly later than the mineral ization of the district. The vein at the Sawbill shaft has a strike N E., dip 85 0 E. It is exposed for fifty feet to the north, but was not seen to the south. The width is thirty-two to thirty-six inches of quartz, milky or waxy in appearance and containing little sulphide. The country rock is a fresh quartzose granite, altered near the vein to a greenish rock with zones of slickensiding, with much chloritic material.

37 33 Cubes of pyrite and some chalcopyrite occur in the altered rock. James A. Bow describes the vein underground as follows: The vein underground ranges from two to five feet in width and averages three and a half to four feet. It has widened near the bottom of the shaft [at that time 230 feet] to six feet. 1 Three samples from the Sawbill vein gave the following assays: No. l Gold, a trace. No Gold, #2.80 per ton. No Gold, 40 cents per ton. At the Hammond Reef, it was difficult to see the character of the ore zone at the open-cut south of the crushing plant on account of the vertical walls and the water in the pit. At the small pit marked "2" on the map, it was possible, however, to see the type of material that had been worked. This open-cut is twenty to twenty-five feet wide and a hundred feet in length on a sheared zone in the granite, striking northeast-southwest and with the major fractures dipping 800 S.E. The fractures in the granite are filled by quartz stringers, so that in the most severely sheared part of the zone, quartz forms about one-half of the whole rock mass. Pyrite occurs in the rock fragments. At the large pit south of the crushing plant, the width of the shear zone is about two hundred feet. A sample, taken across eight feet of the central part of pit No. 2, gave neither gold nor silver on assay. J. W. Greig has the following notes as a result of the detailed work: Running northeast across these rocks [granite] is a wide zone in which the granite is sheared and altered. This zone is not sharply defined, and altered rock grades insensibly into unalteied. There are considerable areas of very slightly altered rock and narrow strips in which the altera tion has been intense. In any section across the zone, there will be found one or two such intensely altered places, but they are not continuous, but one tapers out and another begins and they are not in alignment. Roughly a line running about 200 feet southeast of the corner posts in the southwest part of the mapped area, 400 feet southeast of the corner posts near No. l open-cut, about 100 feet southeast of the swamp, along south of the assay office and so on to the northeast would mark the southeast edge. The northwest edge follows the rock northwest of the road, which runs southwest from the crushing plant and is about 150 feet northwest of the mill, and so on to the northeast. There seems to be a more intense shearing along the northern edge, and the vein quartz which cements the fragments is localized in quite definite and narrow zones. Open-cuts Nos. l and 2 seem to be on areas of the greatest amount of replacement by quartz, and there is considerable quartz at No. 3 open-cut, but between that and the shaft there is very little. It is probable that parts of this shear zone contain some gold, and the immense tonnage available makes the deposit an attractive one. On the other hand, the company which operated the property does not seem to have found any part of the zone to be of ore grade, and the negative sample reported above was taken at one of the most favourable-looking parts. Sunbeam. The Sunbeam mine (A.L. 282), situated twelve miles northwest of Hematite on the Canadian National railway, was visited, but no detailed map was made. This mine produced some gold from a 10-stamp mill erected near the lake and about three-quarters of a mile from the mine.. Work was discontinued in During operations, a vertical shaft was sunk on the side of the hill; 180 feet from it and thirty feet lower, an inclined shaft was sunk at an angle of SO 0 towards the vertical one, so that it should intersect it at about 180 or 200 feet. Ore was apparently loaded from the incline on to cars by which it was taken along the tram-line to the mill. The rock is a coarse grey granite, which includes fragments of a darker coloured variety. A very dark coloured granite outcrops 200 feet west of the!qnt. Bur. Mines, Vol. VIII, pt. l, 1899, p. 88.

38 34 shaft. No greenstone appears along the tramway to the lake, but at one place thirty chains from the mine a zone of dark granite is cut by a lighter coloured variety. The rock on the dump is much altered and iron-stained and contains a good deal of chlorite. Along slickensides, a deep-green micaceous mineral has developed that resembles chromium-bearing mica. The quartz on the dump is white and milky with some iron stains. The vein according to descriptions published was four to five feet wide and the values occurred in short shoots. 1 The country rock of the location is grey biotite granite through which the vein occurs as a true fissure, striking northeast and southwest, with a dip of about 50 0 N.W. The original faulting movement left well-defined walls with selvage at an average and fairly uniform width apart of about eight feet and altered most of the granite between to chloritic schist, although in places a badly weathered crushed granite is the only result. Embedded throughout this schistose band, and for the most part in or near the centre, lies the quartz vein, which varies by lenticular expansion from less than a foot to eight in width, but averaging underground in the north east drift, first level, about three feet, and in the southwest drift an almost uniform width of two feet. In that part of the vein down which the shaft has been sunk, the quartz band is con siderably narrower than in any other exposure, averaging above the level about one foot and a half and below varying from one foot to two and a half to within fifteen feet of the bottom [207 feet at that time], where it pinches to a few inches followed by a separation into several smaller stringers. Besides this main vein, there are other quartz bands lying on either side and along one or other of the true walls of the fissure, but seldom over a foot or so in width and not at all continuous. The immediate walls of the main quartz lead are composed of a mixture about one foot wide of finely banded quartz and schist stringers and brown calcite, the quartz, both here and in the main bodies, being white and barren except for occasional pockets or seams of brown calcite and red and green chlorite fibres. The lack of all sulphides beyond an occasional sprinkling of pyrites and galena is noticeable. 2 Manitou Lake Area General Geology The geology of the Manitou Lake area was studied by W. Mcinnes, and summaries of his results were published in the Annual Reports of the Geological Survey for 1895, 1896, and A. L. Parsons examined the geology in some detail with reference to the gold mines, and his succession differs in some respects from that of Mcinnes. The chief point of difference is in the interpretation of the fragmental-appearing rocks at the north end of Trafalgar bay. In the early description, the relation ships of these were not made clear. Parsons clearly states that the so-called agglomerate is really a brecciated portion of the quartz porphyry. This seems to be the correct interpretation. 3 The quartz porphyry is properly a granite porphyry as will be seen from the microscopic examination. Neither Mcinnes nor Parsons states definitely whether or not it is intrusive into the basic rocks. The contact between brec ciated porphyry and altered lavas is covered by low land along the valley of the creek from Beaver lake. Dikes of rock of very similar composition cut the greenstone near the Jubilee vein and again directly south of the Laurentian mine. Dark-coloured dikes cut the greenstone, but their relation to the granite porphyry is not known except by comparison with the Wabigoon area, where they are earlier and are cut by the granite. The geological succession for this small area is as follows: (Granite porphyry, massive and brecciated. PRE-CAMBRIAN j Lamprophyric dikes. (Greenstone.!Ont. Bur. Mines, Vol. XIII, pt. l, 1904, p W. E. H. Carter, Ont. Bur. Mines, Vol. XI, 1902, p Qnt. Bur. Mines, Vol. XX, pt. l, 1911, p. 178.

39 35 Mining Properties Laurentian, Big Master, and Jubilee. The Laurentian, H.P. 371, which began operations in October, 1903, was rapidly developed, and a 20-stamp mill was installed and put in operation in May, On the 1st level, rich ore occurred in a narrow vein, in parts of which there was more gold than quartz. Production continued fairly steadily until November, 1909, when the mine went into receivership. In 1911, a little work was done; and in 1913, the Great Golconda Mines Company, Limited, took out and milled some ore from the old workings. The Dominion Reduction Company dewatered and sampled the workings early in 1916, but no work was done and their option was not exercised. The Big Master mine consists of claims H.P. 366, 367, 368, 369, and 373. No mention of it is made in Government reports previous to 1900, when it is stated mining operations were suspended to install new machinery, and ap parently the mine had then been in operation for some time, as the amount of development described was considerable. After the installation of the plant, which included a 10-stamp mill, operations proceeded steadily with some gold production until The mine remained closed for over a year and was then again operated from April, 1905, to January, It was pumped out for examination in Again in 1916, the Big Master was examined by the Dominion Reduction Company at the same time that that company sampled the Laurentian. Geology of the Laurentian and Big Master properties is shown in the accompanying map. The oldest rocks are greenstone, much of which is a dense, greenish-grey rock. Ellipsoidal weathering is not common, but was observed on the outcrop west of the Laurentian mine buildings. A sample from the tunnel in the side of the hill south of the Laurentian appears under the microscope as a mass of fibres of serpentine in sheaf-like forms. The serpentine seems to have come from chlorite as there are still cores of that mineral left in the bundles of serpentine fibres. In certain zones the greenstone has a decidedly porphyritic appearance with large angular to rounded white masses. Much of this sort of rock is to be found on the dump at the Big Master shaft, and a band of similar character lies directly north of the shaft across the swamp and probably is the continuation of the one at the shaft. The borders are not sharp, but the porphyritic rock grades into the massive. Under the microscope, the phenocrysts appear as a greyish, almost opaque mineral, probably secondary, but from an unknown original. The groundmass is a felt of serpentine and chlorite and is similar in mineral make-up to the massive greenstone. Granite porphyry forms the western shore of Trafalgar bay. It weathers to a light-grey, and small phenocrysts show distinctly on the weathered surfaces. Under the microscope, the texture is porphyritic, with well-formed phenocrysts of both orthoclase and plagioclase in a fine-grained groundmass, in which there seems to be considerable quartz. Ferromagnesian minerals are not abundant and now consist of chlorite and epidote. Sericite has formed from the feldspars. The consolidated rock of the north shore of Trafalgar bay and of the country northward from the bay appears fragmental with rounded boulders resembling the porphyry included in a matrix, commonly somewhat darker and greenish in colour, but still also very similar in composition to the porphyry. Parsons in his examination of the district came to the conclusion that this rock was formed by the brecciation of the massive porphyry, since it grades into the massive rock without any definite contact. That explanation is believed to be the

40 36 true one, and this rock is really only a crushed facies of the granite porphyry. On the map, however, it is shown in a separate colour, as there is a considerable physical difference between the crushed and massive rock. Dikes of lightcoloured rocks occur on the Jubilee property and between the Laurentian and Big Master. A sample from the former appears porphyritic under the micro scope with rather small phenocrysts of orthoclase and plagioclase set in a ground mass of feldspars and quartz. The large dike which outcrops between the Laurentian and Big Master shafts consists of rock that is porphyritic, but with phenocrysts which are larger than those in the Jubilee dike and which are all plagioclase. The groundmass is similar in both occurrences. Sericite has developed plentifully, and some secondary quartz is present. Cubes of pyrite are scattered here and there in the specimen examined. These dike rocks are so similar in character to the porphyry west of Trafalgar bay that there seems little doubt that they are tongues from it. They are plainly intrusive into the greenstone. Most of the dark-coloured dikes are small; the only one of sufficient size to show on the map runs nearly due north across the tree-covered hill of green stone which lies east of the creek and north of the road from Gold Rock to the Laurentian mine. This rock is a diabase with faint-green pyroxene and lathshaped crystals of feldspar. The dike cuts the greenstone, but its relation to the granite porphyry is not known. The veins of the Laurentian and Big Master system trend slightly east of north. At the Laurentian shaft, the vein cannot now be seen, but following the road north from the houses a vein is exposed by pits just west of the road, and two small parallel veins lie somewhat to the east. The strike of these veins would carry them near the Laurentian shaft if they continue that far. The vein in the pits consists of two lenses of quartz, the eastern one ten inches wide and the western four inches wide, separated by three feet of rather rusty chloritic schist. A second pit 200 feet to the north exposes eighty inches of solid quartz. A sample taken across the face of this pit gave no gold and only a trace of silver. Published descriptions of the underground workings state that the ore occurred as exceedingly rich stringers of quartz in zones of schistose rock. The ore body consists of bands of quartz varying from a mere trace up to several inches in width.... Occasionally schistose bands are found which, when quartz is present in thin stringers, may be regarded as ore bodies. The width of the principal vein is as much as forty feet, but will probably not average more than twenty feet. 1 The total amount of quartz seems to have been very small. It is reported and is apparently true that much gold was stolen. The production is reported as follows: - PRODUCTION OF GOLD FROM THE LAURENTIAN MINE #26, , , , Total , Little quartz remains on the dump, and apparently all that was of any value has been put through the mill since. A sample left in the bins carries only a trace of gold. The tailings from the milling are rather coarse, and high losses would be expected. A sample from the surface of the dump gave only eighty cents per ton, but the lower part may be somewhat richer.!a. L. Parsons, Ont. Bur. Mines, Vol. XX, pt. l, 1911, p. 182.

41 37 The Jubilee vein has been opened at a point a short distance north of the Big Master mill, and a shaft has been sunk at a point where it is four feet in width. Southwestward, the vein is exposed for about fifteen feet, and in that distance it narrows to three feet. A large proportion of the material is quartz, which is white, vitreous, and with only a small quantity of pyrite in it. The schistose wall rock, however, contains sufficient sulphide to cause it to weather red. Two hundred feet to the northeast, a pit on the same vein shows a sheared zone eight feet wide, of which one-half is quartz of a white vitreous variety, somewhat iron-stained. The walls of the vein consist of sericite schist, which is impregnated to some degree with pyrite. A sample channelled across the vein, near the shaft where the width is four feet, gave an assay of S5 per ton in gold. Another vein or series of veins occurs on the Jubilee property, just east of the Jubilee dike of granite porphyry. The largest of these is a lenticular mass of quartz two and a half feet wide in a band of rusty-weathering schist four feet in width. The Big Master vein is covered by the dump at the shaft, but 200 feet northeast is exposed in a pit as several stringers of quartz one to two inches wide, in a rusty zone four to six feet wide, which contains some siderite and pyrite. The shaft east of the main shaft was sunk on a rusty zone in schistose ellipsoidal-weathering greenstone. At the shaft south of the road to Gold Rock, there is a vein of quartz twenty inches wide, but no sulphides. The Big Master vein or veins, as they appeared underground, are described in various reports of the Ontario Bureau of Mines. The pay shoot, which lies northeast of the shaft, has a length of eighty feet along the vein (2nd level) and an average width of eight feet, both of which dimensions it maintains fairly closely from the surface down. The average value is given as J8 per ton. The big or east vein, lying to the southeast of the above, is also reported to have a pay shoot, which is ninety feet long and about five feet wide, lying directly opposite the one mined in the west vein. These pay shoots are well denned from the rest of the vein in that they each consist of a sudden enlargement of the quartz to about double its width elsewhere. It is stated by the manager that the quartz of the west vein carries values pretty well throughout, but that except at the so-called pay shoot, it is too narrow to mine at a profit. 1 The report for the following year differs materially in the values quoted. The statement is made that the west vein widens from two and a half feet on the surface to nine feet at 285 feet, and that in the vein there is a shoot thirty feet in length on the surface and 156 feet long at a depth of 185 feet, with an average value of Si7 per ton. The east vein along the 85-foot level had a width of twelve feet with a shoot of ore 140 feet long, averaging S8.35 per ton. 2 It may be assumed that the lower value of 8 or thereabouts per ton is more nearly the average value of the ore shoots and that, as stated, only those parts of the vein, where the width increased to four or five feet, could be classed as ore; that is, that where the drift required the removal of wall rock, values were not sufficiently high in the vein to maintain ore grade with the dilution of vein matter with low-grade rock. Manitou Island. During 1924, the Anglo-Canadian Explorers, Limited, were carrying on work on Manitou island in Manitou lake. A dike of lightpinkish rock, which in the hand specimen looks porphyritic, cuts through greenstone and chlorite schist. The dike rock is plentifully impregnated with pyrite. An examination of the greenstone shows that it consists of the minerals commonly found in basic volcanics, chlorite, calcite, some remnants of plagioclase,!w. E. H. Carter, Ont. Bur. Mines, Vol. XIII, pt. l, 1904, p Ibid., Vol. XIV, pt. l, 1905, p. 54.

42 38 magnetite, and some quartz which shows strain shadows and is therefore probably original. Hence the rock was a quartz andesite. The dike rock intrudes the greenstone and sends off tongues into the schistose walls, laterally from the contact. Where not impregnated with pyrite, the colour is dark-grey, but in places where it has pyrite, the colour is pink. Commonly the pyrite is dis seminated evenly throughout the dike, and the rock, when the surface is examined, looks porphyritic with quartz phenocrysts partially replaced by pyrite. Micro scopic examination shows, however, that the quartz does not occur as pheno crysts, but was actually the last mineral to crystallize in the dike rock and is interstitial. The chief other rock-forming minerals were feldspars, which have now completely altered to sericite in which the quartz is embedded, thus giving the impression of quartz phenocrysts. The pyrite may replace the quartz, but it seems rather to have replaced the altered parts of the rock, the embayments into the quartz individuals being merely the filling of the spaces originally occupied by feldspars. The original rock was no doubt an ordinary granite. Quartz stringers up to an inch in width reticulate through the granite. Trenches have been dug transverse to the supposed direction of the dike, but owing to the irregular branching of tongues of the intrusive into the green stone schist, the outlines of the granite are difficult to determine, especially as there is heavy overburden in many places. The southern side of the mass seems to extend at least to the waters of the lake. One of the trenches, forty feet in length, does not expose either wall of the dike. Encouraging values in gold are said to have been obtained, but a sample chipped across ten feet of a part of the dike that appeared as well pyritized as any of the exposed part of it, gave an assay of only eighty cents per ton. Quartz collected from some quartz stringers carried Si per ton. Sakoose. The Sakoose mine, which is six miles south of Dyment, on the Canadian Pacific railway, may be considered as being in the same group as the Laurentian and Big Master. The Sakoose was worked from 1899 to March 15, A spur line connected the mine with the railway, and ore was shipped to the Keewatin Reduction Works for treatment. Northwest from the mine dump, the rock is dense, black, and slaty. The microscope shows the mineral constituents to be actinolite, in bundles of needleshaped crystals, and a small amount of calcite, which forms a sort of matrix for the actinolite. A smaller area of similar rock entirely surrounded by those classed as sediments consists of quartz and actinolite with marked pleochroism from blue to green. Both of these types were probably originally andesitic lava flows. The eastern part of the map-sheet is underlain by banded rocks, some of which are undoubtedly sediments and others may be silicified zones in the greenstone. The sedimentary rocks have narrow bands of light and dark grey, some of which under the microscope have thin streaks and lenses of black material, but others have the dark material evenly distributed. The greater part of the rock consists probably of quartz and sericite, but the texture is too fine for certain determination. Both the lavas and sediments are intruded by masses and dikes of acidic rock. One of these forms the wall of the main vein at several places. In the hand specimen, it is a fine-grained, fresh, greyish rock that weathers pink. Under the microscope it appears decidedly porphyritic with well-formed sharp crystals of quartz set in a fine-grained groundmass of quartz and sericite that no doubt has developed from feldspar originally present. Biotite occurs in some quantity.

43 39 Certain dikes also occur, which are mapped as granite. In the hand specimen, they are dark-grey, granular rocks. They may be differentiates from the quartz porphyry, or a hybrid formed by the inclusion of basic material. At the shaft, the main vein occurs in the quartz porphyry. Northeastward, the walls are the rocks classed as sediments and silicified greenstones. The wall rock is sheared slightly in places, but the alteration is not extensive. The vein is very irregular in strike and dip and varies in width from a few inches to five feet or more. The quartz is an unusual dull-blue colour and rather vitreous. Very few other minerals occur in the vein. Values do not seem to have been high enough to bear the cost of transportation to Keewatin to be milled, and a sample of quartz still remaining on the dump contains only a trace of gold, but it is probable that some parts of the vein carried higher values. Dryden Area General Geology The geology of the Dryden area has been studied by William Mcinnes at various times, and the results of his work have been compiled on the Manitou Lake sheet of the Geological Survey of Canada. A somewhat detailed investigation of the gold deposits was made by A. L. Parsons in 1911, 1 and a further report on the Dryden gold area was made by Ellis Thomson in This last report summarizes the geological succession as follows: 1. Pleistocene deposits. 2. Later diabase and gabbro dikes, probably Keweenawan in age. 3. Later granite: hornblende-biotite granite, probably Algoman. 4. Laurentian: biotite granite or gneiss, for the most part, also a little hornblende granite. 5. Keewatin: (a) Igneous complex volcanics, acid to basic, agglomerates, pyroxenite, etc. (b) Metamorphosed sediments garnetiferous hornblende and biotite schists. In the present work, the geological succession was studied only in the vicinity of the working properties and no examination of regional relations was undertaken. From what was seen, however, the writer has some doubts that two separate intrusions of granite can be distinguished. In addition, there are numerous basic dikes which are earlier than the granite. These points will be made clear in the detailed descriptions following. Mining Properties Contact Bay Mines (Bonanza, Redeemer, Rognon). The property upon which the most work is being done in the Dryden area at present is that of the Contact Bay Mines, Limited, with work concentrated on the claims north of the old Redeemer mine, the mill of which has been used for tests on the ores. A force of twenty-five men was employed during most of 1924, and the mine was in charge of P. R. Whytock, from whom the writer and his party received a great deal of assistance and hospitality. A remarkably complex system of volcanic flows and agglomerates intruded by dikes occurs on the Bonanza and Redeemer claims. The south half of lot 7, concession I of the township of Van Horne, was mapped on a scale of 200 feet to one inch as it was thought that this might form a key section should further K)nt. Bur. Mines, Vol. XX, pt. l, Ibid, Vol. XXVI, 1917.

44 40 detailed work be attempted. The geological section is as follows, neglecting the unconsolidated glacial and recent cover: fquartz veins. PRE-CAMBRIAN j Granite porphyry dikes. } Intrusive contact (Lamprophyre dikes. Intrusive contact Volcanic group of interbedded basic flows, rhyolite tuff, and agglomerate. The areal distribution of these is shown on the accompanying map. The basic flows of the volcanic complex in places show ellipsoidal weathering on a large scale with ellipses having major diameters of three feet. A flow of this character forms the summit of the ridge directly north of the Redeemer shaft-house. No detailed description of this rock is necessary, as it is exactly similar to greenstone described in other places. The acidic flows are fine-grained, white-weathering rocks that on the fresh fractures are grey. In places, as in the band sixty feet north of the Bonanza shaft, there is a distinct ellipsoidal weathering, with ellipsoids of four inches greater diameter. Under the microscope, a sample from the band at the shaft appears as a very fine grained mosaic, probably of quartz and feldspar, with some phenocrysts of orthoclase, which lie near fractures filled with chlorite and calcite. A sample from the rhyolite near the border of the map-sheet directly east of the shaft is even finer in texture and shows no phenocrysts. The flows are now nearly vertical and strike east-west, but no age relationships between greenstone and rhyolite could be definitely determined, and it is not known as yet whether the top of the series faces to the north or to the south. Parts of the rhyolitic bands have been brecciated, as is shown by the gradual transition from massive to fragmental rocks. There are, however, some finely banded types that are interpreted as tuffaceous in nature. All of these f ragmental-appearing rocks are grouped together on the map and the boundaries between acidic flows and fragmental volcanic rocks must be considered as rather arbitrary. The general character can best be appreciated by the description of the borders of one of the bands. Along the north of the band of rhyolite, near Station 11, the rock contains fragments of rhyolite up to two feet in diameter, lying in a matrix that shows flow structure. South of the fragmental zone, the rock is typical massive rhyolite. Along the south side, the rock has banding so fine and regular that no explanation seems possible, other than the thorough sorting of volcanic ash, probably by water. Thin sections were made, both of fragments and of matrix, of some of the coarser agglomeratic or brecciated rocks. Part of the fragment was found to be similar to the rock described above as a rhyolite. It is porphyritic with only a few crystals of orthoclase in a fine-grained groundmass of quartz, feldspar, a fairly large amount of calcite and chlorite, and some magnetite. In addition to the porphyritic part, the same thin section shows areas of finer texture not porphyritic and less transparent than the porphyritic portion. The matrix of the agglomerate is like the finer grained portion of the rock just described. It contains angular fragments of quartz and feldspar and some material which is nearly isotropic and which may be glass. The microscopic examination corroborates the field evidence of a series of rhyolitic flows with lenticular autoclastic and tuffaceous layers. The dark-coloured dikes weather brown with surface alteration extending as much as half an inch into the rock. Beneath the brownish weathering, the rock is dark purplish-grey in colour. Specimens from several dikes were

45 41 examined microscopically. The rock from the large dike shown east of Twin lake is porphyritic, with blocky crystals of a mineral which has altered to a nearly opaque, brownish material. The groundmass is chiefly chlorite and calcite with some quartz. Other dikes from which specimens were examined are the large dike north of the shaft, the still larger parallel dike northeast of that, and some smaller dikes east of the shaft. None of these is porphyritic, but in all the rock is similar to the matrix of the one just described: a felt of secondary minerals, chiefly chlorite and calcite, with some sericite and quartz as constant constituents. Many of the dikes are really sills lying parallel to the flows. Others, however, crosscut the structure, as can be readily seen. They are not all strictly of the same age, as some are found to cut and displace others. They are, however, so similar in appearance and constitution that it is impossible to separate them them in mapping, and, furthermore, they all probably belong to a single period of intrusion. The granite porphyry is a light pinkish rock that is also pink on the fractured surface. Thin sections of specimens from various parts of the tongue that extends northward and westward from the centre of the map-sheet are practically identical in appearance. The rock is decidedly porphyritic with phenocrysts of orthoclase and an acidic plagioclase, in both of which some sericite has formed. The groundmass is crystalline, but finer in texture. It consists of feldspar, quartz showing strain, sericite from the alteration of feldspars, and a very small amount of chlorite representing original biotite or hornblende. The granite porphyry cuts across the bedding of the volcanic group and also sends a few sills out between the flows. The sills, however, do not follow the strati fication for any great distance, as is shown by the lack of parallelism in them. The granite porphyry cuts across the basic dikes and in places faults them. The veins on the Bonanza claims are small and lenticular. On the surface, the main vein cannot be traced continuously, but underground it has been followed for at least 600 feet. In that distance, the variation in width is from two to twenty inches. The quartz is white and vitreous to sugary in character with some pyrite, sphalerite, and galena present, and some gold in visible particles. The wall rock is but little altered; but here and there quartz stringers branch off from the vein along the rather pronounced horizontal jointing. Calcite is abundant in these stringers. Values are erratic, and high assays are obtained from individual samples, but the quartz alone will average probably about S3.50 in gold, so far as the vein has been opened up. As the wall rock is practically barren, mixture of rock with quartz will further lower the grade. The manage ment is at present proceeding with development down to the 400-foot level, in the hopes of encountering a shoot of higher grade material. A large flow of water has delayed work very considerably. The gold has been found to be largely free milling, a mill test at the old Redeemer mill giving an extraction by amalgamation of eighty-two per cent, of the gold content. The veins are somewhat later than the granite porphyry, since the dike west of the shaft is cut by the vein and is displaced horizontally and perhaps vertically as well. It may be that the period of vein formation followed closely on the period of rock intrusion, being only enough later to allow of the fracturing and faulting of already solidified dikes, while the vein-forming activities of the cooling parent mass were still going on. Although little is now being done, considerable work has been performed in the past on the Rognon claims 1 which adjoin the Wachman. A one-stamp i-xotes by H. H. North.

46 42 mill for test purposes has been installed. The rocks are similar to those described in detail in the section farther north. The vein is the continuation of the one on the Wachman property and shows similar variations in size. A shaft has been sunk to a depth of 160 feet at a point where the vein has a width of two feet. Samples taken at a point 400 feet east of the shaft, where the width is one foot, gave no gold or silver. Samples from the dump gave eighty cents per ton in gold. Wachman Claims (from notes by H. H. North). Work was also being done during 1924 on the Wachman claims lying near Contact bay, south of the Contact Bay Mines group. The rocks are similar to those described above with the exception that the granite is greyish in colour. It is the youngest rock exposed. The vein on these claims can be traced practically continuously for a quarter of a mile, with variations in width from one inch to one foot. The strike is east-west, and the dip 85 0 N. Two shafts have been sunk. The eastern one has a depth of 100 feet, and the western, 400 feet west of the east shaft, had reached a depth of eighty feet in the latter part of September. A sample taken forty feet east of the western shaft, where the vein has a width of five inches, gave forty cents per ton in gold.

47 INDEX A PAGE Agglomerate. Dryden area A. L. gold Iocs See Foley g.m. A. L. gold loc See Sunbeam g.m. Algoman formation. Dryden area Rainy L. area , 24 Amphibolite. L. of the Woods area Analyses. Granite porphyry.., Andesite. See Keewatin formation. Andrew bay, gold. See Gauthier gold claims. Anglo-Canadian Explorers, Ltd Anglo-Canadian Gold Estates, Ltd Anticline. Bears Pass, notes and photo , 24 Anzhekumming (Upper Manitou) 1. Geology and mines B Bad Vermilion 1. See also Golden Star m. Rocks Bag bay. See Mikado g.m.; Tycoon g.m. Bald Indian bay Bears Passage, Rainy l , 23 Bears Pass area Map facing 22 Beaver I., Manitou L. area Big Master g. mine Map facing 36 Biotite granite. Dryden area L. of the Woods area Black Sturgeon g.m Bonanza g.m., Van Horne tp. Geological notes Map in pocket Bonanza vein, Foley g.m , 27 Boulder clay. See Pleistocene. Bow, James A , 27, 28 Brent, Charles British Canadian Mines, Ltd l, 25 Bullfrog vein, Sultana g.m PAGE Chlorite schist. L. of the Woods area , 14 Clay, boulder. See Boulder clay. Cleland, R. H " l Coleman, A. P , 7, 8, 29 Contact bay. See Wachman g. claim. Contact Bay Gold Mines Map in pocket Copper. See Chalcopyrite. Cornucopia gold m , 9 Coutchiching formation. Rainy L. area, notes and photo Cross, J. G Crown Reef vein, Sultana g. m. Notes and photo , 19 D Dacite. See Keewatin formation. Daisy vein, Foley gold m Diabase. Dryden area Manitou L. area Diabase porphyry. L. of the Woods area Dominion Reduction Co.: Dorions Isld. g. claim, L. of the Woods. 21 Drift, glacial. See Pleistocene. Dryden gold area. Geology and mining Dyment East Shoal L. area Geology and mining Echo bay, L. of the Woods , 14 Elizabeth gold m Map facing 30 Failures in gold mg., reasons for Felsite schist, Olive g.m Foley g. m Map facing 24 Furse, G. D l C Caldwell, J. F... l Cameron Isld g.m., L. of the Woods. Gold; rocks , 10 Map facing 10 Carter, W. E. H , 14 Cedar isld. See Cornucopia g.m. Chalcopyrite in auriferous veins. East Shoal L. area L. of the WToods area , 20 Champion gold m Chlorite, Seine River area [43] Gabbro. Dryden area Gagne vein, Sultana gold m Galena. L. of the Woods area , 20 Galena vein, Sultana gold m , 18 Gauthier gold claims , 21 Glacial and Recent formations. See Pleistocene. Gold and gold mining. Failures, reasons for Key map showing locations...facing 2

48 44 PAGE Golden Star gold m , 27, 28 Map facing 27 Golden Star Mg. and Dev. Co Golden Horn m Photo Granite. Dryden area East Shoal L. area , 26 intrusive in greenstone L. of the Woods area Seine R. area, petrography Granite gneiss. Rainy L. area. See Algoman forma tion; Laurentian formation. Granite porphyry. L. of the Woods area Manitou L. area , 35 Granodiorite. L. of the Woods area Greig, J. W , 23, 33 Greenstone. E. Shoal L. area , 28 L. of the \Voods area , 8, 15 Manitou L. area , 35 Rainy L. area Seine R. area , 31 Greywacke. See Seine series. H... Hammond Reef gold m , 33 Map facing 32 Harold 1. See next ref. Harold Lake gold m , 32 Helldiver bay. See Olympia g.m. Hematite, Ont , 33 Hilly Lake gold claim Hornblende-biotite granite. Dryden area Hornblende schist. L. of the Woods area H. P. gold Iocs., , 373. See Big Master gold m. H. P. gold loc., 371. See Laurentian Jubilee gold m Jumbo vein, Foley g. m K Keewatin formation. Dryden area L. of the Woods area ,4 Rainy L. area , 24 Shoal L. area , 27 Kenora. Gold mg. E. of , 21 Key map, showing gold deposits of facing 2 Kenora dist., gold , Keweenawan formation. Dryden area Rainy L. area L Lake of the Woods area. Geology and mining PACK Lamprophyre. Dryden area East Shoal L. area Manitou L. area Rainy L. area Laurentian. 22 Dryden area Shoal L. area Laurentian gold m , 36 Map facing 36 Lawson, Andrew C , 22-24, 28 Lead. See Galena. Little Turtle lake M Machin, Col. H. A. C l Mcinnes, William , 39 McXeill, W. K Manitou isld. and lake Manitou lake, Upper. See Anzhekumming 1. Manitou Lake area. Geology and mining Maps. See ulso the various mines. Bears Pass area, R.R. dist.....facing 22 Contact Bay Gold Mines in pocket Gold deposits, dists. Ken. and R.R., key map facing 2 Margash Mikado g.m. History Map facing 4 Photos , 5 Mine Centre North, H. H l, 41, 42. O Olive gold m Map facing 28 Olympia gold m Map facing 4 Photo Ophir gold mine , 20 Map facing 16 Parsons, A. L.....3, 4, 8, 10-12, 25, 34, 35, 39 Pleistocene deposits. Dryden area Porphyry. See also Granite porphyry; Quartz porphyry. L. of the Woods area Pre-Cambrian. See also Algoman, Keewatin, Ke weenawan, and Laurentian forma tions. Dryden area Manitou L. area Pyrite in auriferous veins. Dryden area East Shoal L. area , 28 L. of the Woods area , 15 Upper Seine R. area

49 45 Pyrrhotite in auriferous veins. L. of the Woods area PAGE 10, 20 Q Quartz diorite. L. of the Woods, petrography Quartz porphyry. L. of the Woods area , 16 Quartzite. E. Shoal L. area, notes and photo R Rainy Lake area, gold Rainy River dist., gold Recent deposits. See Pleistocene. Redeemer gold m Map in pocket Regina gold m Map facing 12 Photo Rhyolite tuff. Dryden area Rice lake, Seine r Rognon gold claims , 42 Roseburgh, R. M Rush bay. See Golden Horn m. Photo PAGE Sulphides. See also the varieties. Foley gold m Wendigo gold m Sultana gold m. History; geology; mineralogy Map facing 16 Photos , 19 Sultana isld. See Sultana g.m. Sunbeam gold m , 34 Swedish Mining Syndicate T Thomson, Ellis Till. See Boulder clay. Trafalgar bay, Anzhekumming 1. Rocks Trap rocks, L. of the Woods , 7 Twenty-six Mile ck Tycoon gold m Upper Seine River River area. area. V See Seine Sakoose gold m Map facing 38 Sawbill gold m , 33 Map facing 32 Sawbill lake. See Sawbill g.m. Scramble gold m Seine series. Rainy L. area and Shoal L. area....22, 24 Seine River area. Gold mg. reports Shoal lake. See East Shoal lake; West Shoal lake. Siderite in auriferous veins. Upper Seine R. area Sirdar gold m. Granite Reason for working Snake bay, L. of the Woods Sphalerite in auriferous veins. East Shoal L. area L. of the Woods area Stagee, G., g. claims Map facing 24 Van Horne tp. Gold. See Dryden gold area. Veins, auriferous. In granite and greenstone, notes. W Wachman gold claims. Wendigo gold claim West Shoal Lake area. Gold mining White, William Whitefish bay, L. of the Woods. Gold. See Regina g.m. Witch bay, L. of the Woods. Gold near. See Wendigo g. m. Yellow Girl pt., L. of the WToods.. Zinc blende. Y Z See Sphalerite l 21

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