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NVMC Newsletter 2016-03.Pdf The Mineral Newsletter Meeting: March 28 Time: 7:30 p.m. Long Branch Nature Center, 625 S. Carlin Springs Rd., Arlington, VA 22204 Volume 57, No. 3 March 2016 Explore our Website! March Meeting: Spring Club Auction In this issue … Mineral of the month: Sylvanite .... p. 2 March program details ................... p. 2 The Prez Sez .................................... p. 3 February meeting ........................... p. 3 Program summary .......................... p. 5 Editor’s corner ................................ p. 6 AFMS: President’s overview ........... p. 7 EFMLS: Car talk ............................... p. 8 Smithsonian National Mineral Collection. Photo: Chip Clark. Humor ............................................. p. 8 NOVA geology field trip photos ...... p. 9 Sylvanite EFMLS: Wildacres in autumn .......... p. 15 from Romania Agate classifications: Part 2 ............ p. 16 Silver‒gold telluride Auction bid slips .............................. p. 18 (Ag,Au)2Te4 Upcoming events ............................ p. 19 Mineral of the Month Sylvanite by Sue Marcus Happy St. Patrick’s Day! When you think of Transylvania, do you think of Dracula—or the more rare and valuable sylvanite? Yeah, me too. Northern Virginia Mineral Club I hadn’t heard of sylvanite until Super Editor Hutch members, came up with the stunning photo on the cover. So I looked it up. Please join your club officers for dinner at the Olive Garden on March 28 at 6 p.m. Sylvanite is a rare telluride mineral with the chemical formula (Au,Ag)2Te4. Wow—according to Mindat, it Olive Garden, Baileys Cross Roads (across from Sky- usually has a gold-to-silver ratio of 1:1! So if it is part line Towers), 3548 South Jefferson St. (intersecting of an ore body being mined, it is money in the bank Leesburg Pike), to the mining company—no wonder there aren’t Falls Church, VA many sylvanite mineral specimens! Phone: 703-671-7507 All tellurides are relatively rare, and visible crystals are even rarer. Our micromounter colleagues have a Reservations are under Ti Meredith, Vice-President, better chance of having a nice sylvanite specimen in NVMC. Please RSVP to me at [email protected]. their micro collections than I do in my macro collec- tion. Tellurium was once called sylvanium and was detect- ed in ore from the Transylvania region of Romania. Club Member Rocks and Minerals Although sylvanium fell out of favor as a name for the element, the mineral sylvanite retained its name. Auction Coming Up! March 28 Program Sylvanite is very soft, with a hardness of 1.5–2, so it is delicate as well as rare. It is also brittle and opaque, ur March club meeting will feature our spring with a metallic luster. It forms monoclinic crystals O with a specific gravity of 7.9–8.3, if you could get Club Member Auction! Proceeds from the auction go pure material to weigh and wanted to break your into the Fred C. Schaefermeyer Scholarship Fund, specimen. which supports students in the field of geology. Photographs of sylvanite show it to be silvery to The meeting will start promptly at 7:30 p.m. (note: nickel-gold in color. Websites list its official color as this is 15 minutes earlier than usual). We will quickly gray, white to yellow, or silver-white. I did not see move through the business part of the meeting so we any photos showing specimens that I would consider can get to the fun! white or yellow. Sellers, come early to help set up the room and your Sylvanite occurs in gold deposits in Cripple Creek, items. Bid slips are contained in this newsletter be- CO, as well as several other Colorado, California, low. Photocopy the page if you need more. Alaska, and other gold-associated localities in the Don’t hesitate to bring a guest or invite nonmembers! United States. Specimens are also noted from gold Although only current 2015 club members are al- deposits on Fiji. Sylvanite is found in many other lowed to sell, the meeting and auction are open to all. places around the world, though never in abundance. And please consider volunteering. The auctioneers, Although sylvanite contains gold and silver, it is accountants, and runners are all volunteers—so help mined only as a byproduct because it does not occur us out here, folks! in sufficient quantities to be an ore on its own. The Mineral Newsletter March 2016 2 Rams horn ing,” the fine art of walking about Australia and col- selenite from lecting rocks for recreation. Chihuahua, Mexico, sold to a In addition to photographs, Steve brought many sam- lucky buyer in ples from his collection of rocks, minerals, and fos- the fall 2014 sils. Thank you for sharing with us, Steve! NVMC auction. Our March meeting won’t have a guest speaker—but we will have our staff of auctioneers presenting geo- logical wonders from around the world for you to purchase. Bring your excess equipment and materials—whether lapidary, mineral, or fossil—to the auction and use the proceeds to acquire treasures that other members are auctioning off. Because this is such a popular event, we will start the meeting earlier than normal— Bring small bills, bid early and often, and help us at 7:30 p.m. move on to the next item. We need to be out of our meeting room by about 10 p.m. Our treasurer, Rick Reiber, is formulating a budget to guide our club’s fiscal endeavors over the coming ** Note Current Club Auction Rules ** year. Once a draft is available, it will be printed in Any member may offer up to 20 specimens or up The Mineral Newsletter for your review and we’ll to 4 flats for auction. vote on it during the following monthly meeting. Each flat is one auctionable item. In the meantime, don’t forget to keep Rick busy: The club gets 15 percent of the purchase price; Send in your dues for 2016! the remainder goes to the seller. Bob Anyone may donate items to the auction to fully benefit the club (no money goes back to the do- nor). The minimum bid is $1 on any item. Bids above February Meeting Minutes $20 increase by $5. February 22, 2016 We start with a silent auction, so look carefully by David MacLean and start bidding. Items with multiple bids during the silent auction will be brought sooner to the vocal auction. President Bob Cooke called the meeting to order at 7:45 p.m. at the Winning bidders must pay for the item promptly, Long Branch Nature Center in Arling- with cash or check. ton, VA. Members approved the minutes of the December 16, 2015, meeting as published in The Mineral Newslet- The Prez Sez ter. (The January club meeting was canceled due to inclement weather.) by Bob Cooke The president recognized guest Eric Sword. Those of you who didn’t make it to last Old Business month’s meeting missed a superb presen- The president reported that past president Wayne Su- tation by club member Steve Hill. kow, who served most recently as club president just Steve lived in Australia for several years last year, is examining the NVMC bylaws for revi- and was actively involved in “fossick- sion. The Mineral Newsletter March 2016 3 Steve Hill: Marine fossils, minerals, and gemstones, Northern Territory and Queensland, Australia Kathy Hrechka: Recently taken mi- crophotographs of snow crystals Announcements The Long Branch Nature Center asked everyone to leave by car slow- ly to avoid interrupting—and render- ing thinly horizontal—the parade of Scenes from the February NVMC meeting. Far right (in the blue shirt) is club member Steve frogs and salamanders that are Hill, who spoke about his adventures while fossicking in Australia. Photos: Sheryl Sims. crossing the access road to the pond for the summer. New Business A fossil-hunting trip was announced on the beach at low tide at Stratford Hall (next to Westmoreland State The president reported that the club board of directors Park on the Potomac River in Virginia) for Saturday, will publish the 2016 NVMC budget in The Mineral March 12. Fossils there include sharks’ teeth and Newsletter. Members will then vote on the budget. bones. The fee for participants is $50. Door Prizes The Make Fair will be held on March 13 at South Steve Hill, the speaker, donated the door prize fossils. Lakes Middle and High School. The NVMC will pre- Door prize winners included Walker Crews, David sent an exhibit called “Rocks Hold the World To- MacLean, Sandy Paik, and Celia Zeibel. gether.” Display Table NVMC dues of $15 per person are due as soon as possible. Gerry Cox: Fossil sea urchin, Lake Texhoma, OK An EFMLS-sponsored weeklong session of classes Walker Crews: Various marine fossils, Gore, AL related to our hobby will be held on May 9–15 at Items on display included various fossils, as well as photos by Kathy Hrechka of snow crystals. Photos: Sheryl Sims. The Mineral Newsletter March 2016 4 Wildacres on the eastern edge of the Blue Ridge Australia is as big as the United States, with about 25 Mountains near Marion, NC. Registration has been million people. Most of the population is in New open since January 2016, so register now! Classes fill South Wales, Victoria, and Queensland on the east up fast! coast. The Delaware Mineralogical Society show will be on Steve’s wife told him he needed a hobby, so he took March 5–6 in Wilmington, DE. up fossicking with the Central Australian Mineral Club. Central Australia has a hot desert climate. Fos- The annual Atlantic Micromounters’ Conference will sicking season is in winter, from April to October. be held on the evening of Friday, April 22, and all day Saturday, April 23, at the Springhill Marriot in On club trips, Steve found fossils of trilobites as well Alexandria, VA.
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