REPORT ON THE SURVEY MRGNETOMETER. STELLA Nos. l-4 CLAIMS. ROSEA c 0 P P ER MINES L T D. ROBERTSON R I Y E R, B. C. April 26, F.J. Hemsworth.

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1 REPORT ON THE MRGNETOMETER SURVEY of the STELLA Nos. l-4 CLAIMS ROSEA c 0 P P ER MINES L T D. ROBERTSON R I Y E R, B. C. April 26, F.J. Hemsworth.

2 Subject TABLE OF CONTENTS KEY XAP... i%l& II\!TRODUCTION... 1 PROPZRTY... 1,@/LAni MAP... IA LOCATION... 2 TOPOGRAPHY... 2 GEOLOGY... 3 HISTORY... 3 MAGNETOMETER SURVEY... -Survey of Grid... :: -Type of Instrument Procedure* Corrections Diurnal Day to Day... 5 MAPPING... 5 CONcLm3IONS... 6 SURVEY MAP... Envelope

4 MAGNETOMETER SURVHY STBLLA Nos. l-4 CLAIMS ROSEA COPPER MINES LTD. ROBERTSON RIVER, B.C. INTRODHCTION During the month of Bprll, 1957, a magnetometer survey was conducted on the Stella mineral claims by the writer, Fred J. Hemsworth, P. Eng., of Pacific 5eophyslcs Ltd. The survey was made at the request of the directors of Rosea Copper Mines Limited (NPL). This report gives a brief description of the claims, outlines the procedure followed in making the geophysical survey and contains plans showing the result of the Information obtained from this survey. In accordance with the Mineral Act, this report and the accompanying map are submitted as assessment credit on the four Stella claims. The four claims comprise the central portion of a group of eleven located mineral claims, known as the Robertson River Group.

6 -2- Particulars of the clafms covered by the survey are as follows:- Nm Tae: Ro, Record No. Record DatQ Stella 1po. 1 A Stella No. 2 ;;:z E Stella No. :: $% Stella No. 2 A :; : LGCATIGR The Stella claims are on the east side of the Robertson River 5 miles south of Mesachle Lake, AX. They are a&out 10 miles by road from the village of Lake Cowlchan, south-central Vancouver Island, and are in the Victoria Mining Division and within the Esquimalt and Nanaimo Railway Land Grant. approximately Latitud?; &%;~~h&~%~~o~ %tolo*. The Stella claims lie north of the confluence of Long Creek with the Robertson River. South of Long Creek are three crown-granted alaims, the Alpha Lot lg, Beta Lot 20, and Taboga Lot 30. These crown grants were staked In 1902 and during the years considerable underground and surface development has been carried out and a number of showings of copper ore have heen exposed. To the north of the Stella claims, the Copper Ridge claims are presently being explored by King Solomon Copper Wnes. &bout cne mile to the east of the Stella claims, the Fraser Proup is under option to Noranda Mines. This company did some geophysical surveys and are currently diamond drilling. Access to the Stella claims Is by Hillcrest Lumber Company s private road for 3 miles from Mesachie Lake, then by a mine road to the western section of the claims. TOPOGRAPHY The Robertson River Valley is about one mile wide. A small part of the Stella claims lies In this valley, but the major portion of the claims covers the steep western slopes.

7 -3- Elevations vary roughly from 500 feet above sea level on the valley floor to 2,000 feet at the mountain top. The area was burned over about 20 years ago and now consists of rotting snags and wfndfalls, blackened by fire, interspersed with a new growth o? small evergreens. The slopes are characterized by limestone or volcanic rock bluffs, and rockslides incjsea by small creeks, so that travel along straight grid lines Is difficult and labor lous. GEOLOGY The country rock is the Vancouver volcanics with accompanying liaiestone belts. Near intrusive stocks of granitic rocks the limestones have been metamorphosed into dlopside-epidote, and garnetlferous rocks, and are considerably metamorphosed. Copper mineralization occurs as contact-metamorphic type orebodies. Minerals are chalcopyrite, pyrrhotlte, pyrite and magnetite with the typical skarn rocks contalnfing garnetite, epidote and wollastlnlte. Since the early 1900 s considerable stripping and tunnelling has been carried out on the Beta mineral claim, adjoining the Stella No. 1 on the south. This work has exposed several showings of high-grade copper ore along contact zones. A few spot magnetometer readings on the Beta orebody gave up to 3,000 gammas over the exnosed ore anr moderate readings (ahout 1,000 gama!as) over the drift covered areas beside the zone. The same geological conditions exist on the Stella claims. Several years ago large pieces of mineralized float were found during road construction, by Mr. Ralph Liebel. The float was uncovered in a gravel pit at the foot of the hill on the Stella No. 2 claim. The pieces of float contained portions of massive chalcopyrite. They were large and angular and it was concluded that the source could not be far distant. Bulldozer trenches were cut across the mountain slope above the discovery place. This trenching was carried out for considerable distance up the mountain, and although additional ore float was found, the lode was not uncovered.

8 rl The writer examined the ground a year ago and recommended a geophysfcal survey as a possible solution to the problem. S?nce Pagnetlte and. magnetic pyrrf(otlta were associated with the ore, the riagnetoneter method was chosen. Survey of Grid A baseline was cut out on an east-west bfiz;lng and stations were established every 300 These stations were lettered alphabetically from west to east, station A being at the lnitlal post of Stella MO. 2 claim. The baseline was 3,000 feet long and extended up the mountain, along the top and down to a northern fork of Long Creek at the eastern boundary of Stella No. 4 claim. Crosslines were run out at right angles to the baseline to the boundaries of the claims. Stations were established every 200 feet on these crosslines although magnetometer readings were taken every 100 feet. All lines and stations were surveyed in by.brunton compass and steel tape. Type of Instrument v The instrument used in this survey was of the Schmidt vertdcal-force type, being a Kodel A-2 Sharpe, havl.ng a sensitivity of 2 gammas and of the latest type with al auxiliary magnet for allgninp the instrument with the earth s maonetlo field as an 1nte:ral part of it. Each scale division represented 20.3 gammas. A further refinement In this model IS the temperature compensating device making It unnecessary to make temperature corrections. The Instrument had ju::t returned from a complete check up and adjustment at the factory in Toronto and was found to be working perfectly. Where large variations occur the instrument is provided with three auxiliary magnets, one oi which can be attached below at various heights assuring a reading at almost any point on the ground. A table gives the corrections to be made for each magnet at different distances below the instrument.

9 -5- Procedure After the lines had been cut and the stations established, two men carried out the magnetometer survey. One man set up the instrument and took the readings. The other noted the readings, and took additional field notes on topography and geology. Although It is possible for one man to do all this, the second man was particularly handy In transferring the instrument over difficult terrain. On two occasions thunder storms interrupted tha work. Wide magnetic differences were noted during the course of the storms so that it became necessary to suspend work and to repeat certain readings on the following day. Corrections (a) Diurnal All readings were corrected for diurnal, or varlatlons from time to time during the day. Since only one Instrument was available for the job, a hase station was set up on the clal.ms. One day was spent in taking readings every hour at this base station and a dlurnal curve drawn from these readsngs. Diurnal corrections for readings taken on subsequent days were based on this curve. (b) Day to Dap: A reading was taken at the base station each day before leaving for the field and each day after field work was completed. The variation between the base reading on any particular day and the original base reading (corrected for dl,urnal variations) was the day to day correction. The diurnal and day to day corrections were added to each field reading to arrive at the corrected magnetometer reading. The result of the magnetometer survey is s lown on the map contalned in the pocket at the

10 back of the report. The magnetometer readings are represented on this map by a series of contour lines indicating the magnetic intensity in gammas. The contour lfnes were drawn through readings of equal Intensity at 100 gamma Intervals on a working plan on nhlch the readjngs were plotted. The 500 gamma fnterval contours were plotted heavier so that a darker line sh~ows jn the print. The map indicates the,(resence of two anomalies. They have a general h 5% strike and are p.arallel. The larger anomaly Is situated at the top of the hill and extends from the Final Post of St&la No. 2 clain northeast for several hundred feet. The smaller anomaly is on the steep slope under the crest of the hill close to the east boundary of Stella No. 2. The highest reading recorded was 1,320 gammas. Readings directly over an exposed orebody similar in compos:~tion to the high-grade float tiould have given readings In the neighborhood of 3,000 gamnias. However as the Intensity varies inversely as the square of the distance from the magnetic source we conclude that either (a) readings were not taken directly over the ore zones or (b) that a considerable depth of overburden has decreased the Intensities. It is recommended that addjtional magnetometer readings be taken in the areas of the anomalies, with statlons t,arked out at 25-foot intervals. These closer-spaced readings Will outline tpe anomalous areas more speclfically and furnish an accurate guide for strlpping and diamond drilling. Respectfully submitted, -*;-.- F.J;/Hemsworth, P. Eng.

11 Statement of Expenses on the Magnetometer Survey of the 4 claims, Stella Nos. l-4, owned by Rosea Copper 'lines Limited, situated at Robertson River, B.C. F.J. Remsworth, P. Eng.-Fieldwork-April 6-17th 1957, 12 A.D. Lietch-1:elper-April ii -loth, 1957, 4 days 0 Vj.OO/day k;.r. Rowbottom-Helper-April 12th & 13th, 1957, F.W. Reger-Draftsman Total $ Certified Correct

Introducti on. Land Survey. Geomagnetic Survey. Geomagnetic Results and Interpretati ons - Conclusions and Recommendations C

Introducti on. Land Survey. Geomagnetic Survey. Geomagnetic Results and Interpretati ons - Conclusions and Recommendations C m M 42A86SW8281 63.42 PRICE 010 C O H T E H l 42A86SW828I 63.42 PRICE 010C Introducti on Land Survey Geomagnetic Survey Geomagnetic Results and Interpretati ons - Conclusions and Recommendations - - -