The Lake George Gem and Mineral Club - Club News, September, 2015

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1 The Lake George Gem and Mineral Club - Club News, September, 2015 Program for the month: Saturday September 12 business meeting followed by a field trip. Our monthly business meeting starts (promptly) at 9 AM and should finish by 9:30 or so. After the meeting, members will gather outside to drive to Goethite Hill, a nearby collecting site known for Pikes Peak pegmatite minerals. Please Note: As some of you are aware, our club is experiencing slight growing pains once again. We now have nearly 400 members! That means that some members have been unable to register for trips. We also have trouble keeping up to date on new members and communicating effectively. The officers recently met to look at what we can do to change things for the better. Some proposed changes will be presented at the October meeting this is important please try to attend! In the meantime, if you receive an from Club, please take the time to read it we have been swamped with queries about things that were covered in s or in the newsletter. Please Welcome the Following New Members Dan Adam Nathaniel & Jeanette Aleman Stephen Avery Amy & Nick Azarov Filip & Valerie Babitz Dawn Beamer Rich Bolen Steve Cain Chris Cormier David Deard Scott & Dawn Hanson Mike & Jean Rose John J. Shepard Tyler Siskowic Chris Sullivan Angie Tipler Ryan Williams Greg Wyman

2 Coming Events Exhibit Opening- Trails and Trials: Stories from the Mining Migration Trails and Ink Sept. 10 Sketches of Mine Labor Life at the Western Museum of Mining & Industry, free lecture By Lee Whiteley,doors open at 6; talk at 7PM, rsvp to or Dinosaur Discovery Day; Geohazards Day, at Dinosaur Ridge, Morrison, CO, 10AM- Sept. 12 2PM; go to for info. Denver Coliseum Mineral, Fossil, and Gem Show, see Sept Colorado (Fall) Mineral and Fossil Show, Ramada Plaza Hotel (formerly Holiday Inn - Sept Central Denver), 4849 Bannock St, Denver, CO; see Canon City Geology Club Auction, First U.M. Church Fellowship Hall, cor. 9 th & Main Sept. 14 6PM. Everyone welcome. "The WHAT of conodont science: Insights into Permian oceans and beyond, by Sept. 15 Charles Henderson, 3:00 p.m., DMNS Earth Science Seminar, Univ. of Calgary. Free lecture; museum admission not required. Annual Open House, CSM Geology Museum, 6-9PM, for more info, go to Sept Denver Gem and Mineral show, at The Denver Mart, 58 th Ave. and I-25 (ext 215) Sept sponsored by the Greater Denver Area Gem and Mineral Council; dealers, exhibits by clubs, individuals, and museums nationwide; lectures, demonstrations, and kids activities; theme, Minerals of the American Southwest. 9-6 Fri., 10-6 Sat., 10-5 Sun. See (admission charge; free parking and shuttles to other shows) Lake George Gem & Mineral Show Observations. By John Rakowski Rebecca Blair arranged a good selection of dealers this year. An individual who himself manages a number of mineral shows throughout the US was quoted as saying that the mineral selection from several of our dealers surpassed the quality and variety available at another entire local show that weekend. The general feedback from dealers at our show is that they were very pleased with the site, the help from Club members and their sales. Most are eagerly looking forward to next year s show. Char DeVries did a great job in coordination of the club volunteers working at the show. We had many new people who pitched in, learned quickly what needed to be done, and really helped out. This is a great way for new members to learn more about the Club, other members, and the hobby in general. Some of us older members got a chance to spend more time with new members and learning from them as well as providing some insight and mentoring of the hobby to the new folks. On the weekend before the show, we had a good group of volunteers to mark out the spaces and set up the necessary flagging and signs. The work goes quickly when we have eager volunteers. The volunteers got more of an insight into what goes into show preparation. During the show, we had many visitors to the club booth inquiring about the LGGMC. There were a number of delighted faces of the youngsters who received specimens donated for kids, including the Study Bags made by the Leidys and Greenes. It is very important to share our hobby and to let the public know the types of family activity that we enjoy. The thrill of finding minerals formed many millions of years ago is amazing to all of us. We all owe a profound g{tç~ léâ to The Lake George Company for allowing the use of the field for the Show. Lyle Johnson, who started the company and purchased the land, was an avid mineral collector and club member before his death several years ago. He felt that a show is important for a club, and he graciously made a part of his land available. Many Thanks!

3 We ll be looking for volunteers to help with next year s show. There is a detailed how to list to follow and experienced Club members to help you with the duties. Please consider being available to help out Your show doesn t just happen out of the blue without guidance or contribution. The Annual Show was a big success! By Bob Carnien There were 26 dealers selling all kinds of interesting Earth-science-related specimens, jewelry, and collectibles (see photos below). We kept count, and there were over 1300 visitors for the 3-day event!. Jean Cowman & Rich Fretterd; goodies galore for the kids. (Ingrid Hamilton photos) Kendra Wilson s busy booth; Let s See?? (too many choices!) (Ingrid Hamilton photos)

4 Pebble Pups and tiger eyes welcome! (Carnein photos) Cool fossils from Porter s Rocks and Fossils and Pangaea Rocks (Carnein photos)

5 Jewelry from Raindance Traders, beads from Maxx Roxx, and a fantastic tourmaline specimen from Ray Pohlhotte (Carnein photos) Everybody appeared to have a good time! (Carnein photos) Kendra Wilson and the Leidys had some great local material (Carnein photos)

6 Norma, Jo, and Char appreciating a specimen. A spectacular columbite crystal found by a local collector. (Carnein photos) We greatly appreciate participation by the following Show Dealers: Amazing Rocks & Minerals Stephen Avery Gary Darpel Ike Frank Rich Fretterd & Jean Cowman Kent Greenes Mary Beth Griffin Dave & Lark Harvey Dave & Linda Leidy Maxx Roxx Veronica Michels Ken Newman Pangaea Rocks Jay Penn Ray Pohlotte Randy Porter Raindance Traders Julieta Ruiz Santa Fe Silver & Stone Doug St. Pierre Claudia Umpleby Dennis Whitney Gary Williams Kendra Wilson Some of these may be duplicates, and I may have missed one or two; please let me know and I ll include them in the October newsletter.

7 Here s a photo from Glen & Rita Stubert of the August 15 dig at the Topaz Mountain Gem Mine. Remember the following Pikes Peak Pebble Pups talks at the Denver Gem & Mineral Show, Sept. 18: Saturday Noon Pikes Peak Pebble Pups Casey Martin Radioactivity in Colorado Dinosaur Fossils. Jack Shimon Radio-Wave Powered Crystal Radio. Blake Reher Advances in Pikes Peak Regional Paleontology. Jerrod and Nathan Gallup After the Eruptions: Mt. St Helens and Crater Lake (Mt. Mazama). Here s a list of planned Field Trips, as of September 1: Sept. 12: Goethite Hill (tentative) Trip Leaders: Kent Greenes; Dave Leidy Sept. 26: Holcim Quarry (tentative) A slate of nominees for next year s officers will be presented at the October meeting. We have volunteers for some positions, but nominations (or self-nominations) are always welcome. Besides the regular officers (President, Vice President, Treasurer, Secretary, and Newsletter Editor), we are looking for volunteers for the following positions relating to the annual show: (1) Pre-planning (arranging porta-potties, field mowing, liability insurance, etc.); (2) management of physical assets (signs, spray paint, flagging, stakes, etc.); (3) volunteer coordinator; (4) marketing/publicity; (5) overall show coordinator (overseeing all of the above). Rebecca Blair did a great job keeping the show organized this year, and will be on the Show Committee in charge of dealers/vendors in It has been reported that some LGGMClub members are digging pretty aggressively at the Wigwam Creek claims. This is a reminder that the Club claim is ONLY FOR SMALL-SCALE DIGGING BY CLUB MEMBERS. No one should remove more than a bucket of material, and overly abundant visits are discouraged. Remember that we have nearly 400 members. If you want to collect quantities of samples, it is your responsibility to find and stake your own claim. Also, remember that you MUST REPORT to Dan Alfrey ( AlfreyDan@aol.com ) before and AFTER you visit the claim. Some new members may not realize that we have had (major) issues with the Forest Service we do Not want that to happen again. And here is the latest installment of Bench Tips by Brad Smith ( SMOOTHING EARWIRES Any time I make my own earwires, the hardest part for me is to sand and polish the end that's inserted into the ear. Any sharp edge there is no fun. I've tried using sanding sticks, cup burs, and silicone polishing wheels. I've tried buffing on a Zam wheel, and I've tried spinning the wire in the Foredom to polish the tip. While all of these techniques do the job, none are very easy, and none are as fast as I'd like. Then it occurred to me - I could melt the wire smooth. One quick touch in the flame of the propane/oxygen Little Torch does the trick - not enough to form a bead on the wire but just enough to round off the tip. I find it's worth practicing the maneuver a couple times on some scrap wire before trying it on completed earrings.

8 BALL BURS I use ball burs quite a bit for carving and for cleaning up bits of solder that need to be removed. The ball shape seems to be more controllable than other cutting burs. They're less apt to grab and walk over your piece. As to sizes I've found that 8 mm is a very useful size for carving, while a half mm or smaller at high speed works great for signing your name on the back of your work. ========================================= Get all 101 of Brad's bench tips in "Bench Tips for Jewelry Making" on Amazon. Notes from the Editor Bob Carnein, Editor ccarnein@gmail.com This month, we have an article by yours truly about an underappreciated rare mineral sometimes found in the pegmatites of the Pikes Peak batholith. Keep your eyes open, and you might find this lurking among your smokies and amazonites. Phenakite: an Elusive Pegmatite Mineral by Bob Carnein Lake George Gem and Mineral Club September, 2015

9 Phenakite (aka phenacite; pronounced feen -uh-kite) is a rare beryllium silicate mineral (formula Be 2 SiO 4 ) that occurs as excellent crystals at several Colorado localities. For the beginning collector, it s one of the most difficult minerals to identify, commonly being confused with the much more common quartz and topaz. This article is designed to help you to recognize this elusive and often overlooked mineral. Figure 1. Small (5 mm across) phenakite crystal from Palelni mine, Myanmar, showing hexagonal shape. (Carnein collection and photo.) Properties. The name phenakite comes from the Greek phenakos, meaning a deceiver, because of its resemblance to quartz (Klein and Hurlbut, 1999). Phenakite occurs in the rhombohedral division of the hexagonal crystal system. If you look carefully, crystals are usually clearly hexagonal (Figs. 1, 2), which helps one to distinguish phenakite from topaz, whose orthorhombic crystals are often rectangular or diamond shaped in cross section. Be aware, though, that some topaz crystals look superficially hexagonal. Both minerals commonly exhibit vertical striations, unlike quartz, which has horizontal striations on its prism (vertical) faces. Unlike topaz, phenakite is often twinned, in which case its crystal terminations may resemble an old fashioned star drill (so-called drill-bit twins; Fig. 3). Terminal faces are usually gently inclined, compared with the more pointy terminations on quartz crystals (Figs. 4, 5). Phenakite crystals from some localities have a flattened, lensoid shape (Figs. 6, 7). Phenakite s hardness is 7.5 to 8 very close to that of topaz (number 8 on the Mohs scale) or quartz (number 7). All three easily scratch glass or steel. Its specific gravity varies between 2.93 and 3.0 (Anthony, et al., 1995), which helps to distinguish it from topaz (3.49 to 3.57) and quartz (2.65). To the experienced collector, topaz (except in small crystals) feels a bit heavier than expected,

10 Figures 2 and 3. Small (2.3 cm x 5 mm) prismatic phenakite crystal from Myanmar, showing drill-bit twinning. (Carnein collection and photos.) while phenakite does not. Phenakite crystals usually are too small for this to be of much use. Unless you can actually measure the SG, quartz is too close to phenakite to use this property to tell them apart. Phenakite s color varies from colorless to yellow, pink, or brown. None of these colors help to distinguish it from topaz. However, topaz is often pale blue or greenish blue, which is very rare in phenakite. Quartz occurs in so many different colors that color, alone, usually isn t helpful in Figures 4, 5. Large (2.9 cm x 1.3 cm) phenakite crystal from Myanmar, showing simple rhombohedral termination. (Carnein collection and photos.)

11 Figures 6, cm flattened, lenticular phenakite crystal from Bear Creek Canyon, near Specimen Rock, El Paso Co., Colorado (top and side views). (Carnein collection and photos.) distinguishing it from phenakite. However, phenakite is rarely strongly colored (unlike, for example, smoky quartz or amethyst). Both phenakite and topaz have cleavage, but that of topaz is much more obvious (perfect) and is perpendicular to the long axis (c axis) of its crystals ({001}). In phenakite, cleavage may occur in several directions, none of which are perpendicular to c. The cleavage is rarely apparent (Hurlbut and Kammerling, 1991). More commonly, like quartz, it exhibits conchoidal fracture. All three minerals are commonly transparent to translucent. This and their high hardness and moderately high indices of refraction make phenakite and topaz useful gemstones. Quartz is also cut and polished, but its low RI makes it a bit dull. Phenakite has more sparkle than topaz, but this usually isn t apparent in an uncut crystal. Although phenakite isn t nearly as familiar to the general public as topaz, gemstone connoisseurs appreciate its greater rarity and will pay a premium

12 Figures 8, 9. Very fine etched phenakite crystals from the Jos Plateau, Plateau State, Nigeria. (commons.wikimedia). (up to about $300 per carat at present), especially for large stones, which are rare. If offered an expensive gem phenakite, it behooves the collector to test its specific gravity, which is the simplest way to distinguish it from the much commoner quartz or topaz. Occurrence. Phenakite s mode of occurrence overlaps that of both topaz and quartz. All three minerals commonly occur together in granite pegmatites (very coarse grained granites), though quartz and, to a lesser extent, topaz also occurs in many other kinds of deposits. All three also occur in greisens (rocks formed near the contacts of bodies of granite, where high temperature fluids from the granite invade and profoundly alter the composition of the host rocks). In greisens, they aren t likely to occur as good crystals the three minerals may be very difficult to distinguish when massive. Although small amounts of phenakite occur at many locales, the world s best crystals currently come from the Jos plateau, Nigeria and the Mogok gem tract in Myanmar (formerly Burma). Superb, large (up to several cm), transparent, colorless to pale yellow, etched phenakites from Nigeria (Figs. 8, 9) have, for the last decade, set the standard for the world. These crystals don t look much like those from anywhere else but may be mistaken for etched topaz or pale colored garnet. Crystals from Myanmar typically are simple, short to elongate prisms that, more often than not, exhibit drill-bit twinning and complex terminations (Figs. 1-3). Other great world-wide occurrence include Russia (Yekaterinburg and Miass), Norway (Kragerö), Brazil (various mines in Minas Gerais), and Madagascar. In the United States, the finest phenakites come from North Chatham, NH; Amelia, VA; Chaffee County, CO (Mt. Antero and Mt. White); and Teller and Park counties, CO (the Crystal Peak area). Mt. Antero continues to be especially productive, but the comparative rarity of phenakite from the Crystal Peak area may be partly due to the fact that many collectors don t know how to recognize it. The writer recently purchased a topaz from Bear Creek Canyon, El Paso County that turned out to be a nice lensoid phenakite crystal (Figs. 6, 7). Although the buyer recognized the crystal when it was offered, the dealer was somewhat surprised when informed that it wasn t topaz. Colorado localities (from Eckel, 1997) include the following:

13 Chaffee County: Mt. Antero and Mt. White, with beryl, bertrandite, quartz, potassium feldspar, albite, topaz, and fluorite. Mainly prismatic crystals, some twinned, to a bit more than 1 inch in length. Most are milky white and many are dominated by rhombohedron faces (Figs ). Figures 10, 11. Two fairly typical phenakites, and (Fig. 12) phenakite on smoky quartz from Mt. Antero. ( El Paso County: Crystal Park (first US find, about 1880), as large (up to 3 inches across) broken rhombohedral crystals found in the 1880s, with topaz, zircon, amazonite, and smoky quartz. Also occurs at Bear Creek Canyon, Cameron Cone and Hunters Run, near Specimen Rock. Park County: Spruce Grove Campground locality, as inclusions in topaz; Crystal Peak area, with amazonite, smoky quartz, topaz, and zircon (Figs. 13, 14); Harris Park, with albite, amazonite, and topaz; Tarryall Mts., as inclusions in topaz; and Badger Flats area, in beryl-bertrandite greisens on smoky quartz. Teller County: Crystal Peak area, as small, flat, highly modified pale yellow to gray to colorless crystals perched on amazonite, with smoky quartz, albite, topaz, and iron oxides. Figures 13, cm phenakite cluster on amazonite, Park Co., Colorado. ( References Cited.

14 Anthony, J.W., et al., 1995, Handbook of Mineralogy, Volume 2: Silica, Silicates, Part 2: Tucson, Arizona, Mineral Data Publishing. Eckel, E.B., updated and revised by R.R. Cobban, et al., 1997, Minerals of Colorado: Golden, Colorado, Fulcrum Publishing. Hurlbut, C.S., Jr., and R.C. Kammerling, 1991, Gemology, 2 nd Edition, New York, John Wiley & Sons, Inc. Klein, C., and C.S. Hurlbut, Jr., 1999, Manual of Mineralogy (after J.D. Dana), 21 st Edition: New York, John Wiley & Sons, Inc.

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16 MEMBERSHIP APPLICATION Lake George Gem & Mineral Club Box 171, Lake George, Colorado Date: Name / /20 Address City State Zip Telephone ( ) - ( Required to receive Newsletter and Field Trip info.) Names/Ages of family members (if family membership): ~ Dues for Jan. 1 through Dec. 31 for each year are as follows: Individual (18 and over).. $15.00 Family (includes dependents under age 18).... $25.00 Due are Due (on) January 1 st. Members w/ unpaid dues by March 31 st will be deleted on April 1 st. On/After August 15, dues will be pro-rated by one-half for NEW members only. I agree to abide by Club Constitution, By-Laws, and Rules regarding Field Trips & Club Claim visits: Signed Date: / / I am or have previously been a Member of Lake George Gem & Mineral Club. Yes No My interest areas include (check all that apply): Minerals Fossils Lapidary Micromounts Colorado Geology Pebble Pups (ages 7-17) Mining History Crystallography Other (be specific): I am willing to give a talk/presentation to [the Club] or [Pebble Pups] on (topic) and/or Lead Field Trip(s) to I am willing to participate/help in the following ways (can choose more than one): Club Officer News Writer-Contributor Annual Gem & Mineral Show Chair/Show Committee Winter Programs Field Trips Membership Coordinator Scholarship/Education Committee Pebble Pups Other (be specific): Questions about the Club or Activities? Please visit the website or contact a Club Officer.

17 Lake George Gem & Mineral Club PO Bo 171 Lake George, CO The Lake George Gem and Mineral Club is a group of people interested in rocks and minerals, fossils, geography and history of the Pikes Peak/South Park area, Indian artifacts, and the great outdoors. The Club s informational programs and field trips provide opportunities to learn about Earth science, rocks and minerals, lapidary work and jewelry making, and to share information and experiences with other members. Guests are welcome to attend, to see what we are about! The Club is geared primarily to amateur collectors and artisans, with programs of interest both to beginners and serious amateurs. The Club meets on the second Saturday of each month at the Lake George Community Center, located on the north side of US Highway 24 on the east edge of town, sharing a building with the county highway shops. In the winter, we meet at 10:00AM. From April through October, we meet at 9:00AM, to allow more time for our field trips. Our organization is incorporated under Colorado law as a nonprofit educational organization, and is a member of the Colorado, Rocky Mountain, and American Federations of Mineralogical Societies. We also sponsor an annual Gem and Mineral Show at Lake George, where collectors and others may purchase or sell rocks, minerals, fossils, gems, or jewelry. Annual membership dues (Jan. 1 through Dec. 31) are $15.00 for an individual (18 and over), and $25.00 for a family (parents plus dependents under age 18). Our Officers for 2015 are: John Rakowski, President Char DeVries, Vice President PO Box Homestead Rd. Florissant, CO Divide, CO rakgeologist@yahoo.com swordfishblue@wildblue.net Suzanne Core, Treasurer Norma Engelberg, Secretary PO Box W. Bijou St. Cripple Creek, CO Colorado Springs, CO suzc@peakinet.net njengel60@gmail.com C.R. (Bob) Carnein, Newsletter Editor 507 Donzi Trail Florissant, CO ccarnein@gmail.com