nldec2008

The Cochise County Rock

Monthly Newsletter of the Sunsites Gem & Mineral Club

www.cochisecountyrock.org

“Finding and Grinding Rocks in Cochise County, Arizona since 1967”

December 2008

This issue edited by Don Hammer

_______________________________________________________________

Sunsites Gem and Mineral Club General Meeting Minutes - November 10, 2008

President, Don Hammer, called the meeting to order at 7 p.m. Don introduced visitors, Glenn and Gayle Renell, Candice Winegard, Dewy and Pamela Southwich and welcomed new members, Orville and Ardy Churchill, and James and Stephanie Baughman. Don asked for a motion to approve the minutes, as published, of the October meeting. It was moved, seconded, and approved.

In Walter’s absence, Don reported that there was one change in the Treasurer’s report given in the November Newsletter, that being, the fee for the Rocky Mountain Federation is $360, not $315. The Treasurer's Report was approved.

Lapidary class is held each Tuesday from 6:30 to 9:30 p.m., Henri encouraged the membership to sign up to join him and Larry in the Lapidary room. Don noted that Silver Soldering is a prerequisite to Silver Smithing. Larry was not present to comment on Silver Soldering, however, Don announced that Silver Smithing will begin in January. This month’s field trip is on November 15. Members are to meet at the Willcox Safeway parking lot at 8:30 a.m., and will be going to Big Joe Canyon near the New Mexico border. We will be looking for honeycolored calcite and copper related minerals. Hammers, chisels, and safety glasses were suggested. The Nominating Committee put forth the following individuals as the Club’s new officers:

President: Paul McKnight

Vice President: Henri van den Bos

Treasurer: Walter Sigel

Secretary: Jim Brower

Member-at-Large: Larry Strout

The Membership moved to approve the new board members. Our Annual Christmas Dinner will be held on December 8 at 6 p.m. As a reminder: if your last name begins with A-H you are asked to bring a salad, I-P a dessert, and Q-Z a vegetable dish. Also, if you would like to participate in the gift exchange, ladies are to bring a lady-appropriate gift and gentlemen a man-appropriate gift - under $10 and gift-wrapped. Sign-up sheets were passed around for upcoming hospitality needs, the Christmas Dinner, the field trip, etc. It was announced that there are jewelry classes being held in Douglas, see Bob Miller for details. Also, literature was made available regarding events being held in Quartzite, Mesa. Don thanked Lou Kidd for providing the refreshments for the evening and the meeting was adjourned at 7:16 p.m. Intermission and refreshments followed.

Our program was the Membership sharing unique rocks, stones, and gems that had interest and significance to them. The Rock Raffle was held after the program.

Respectfully submitted,

Diane Brower

Secretary

Christmas Party

The Club Christmas party will be held on our regular meeting date, the second Monday, December 8. But the meeting time is changed to 6 PM. The Club has two 20 lb turkeys which Karen Grassell and Diane Brower have offered to cook.. If your last name begins with A-H you are asked to bring a salad, I-P a dessert, and Q-Z a vegetable dish. Also, if you would like to participate in the gift exchange, ladies are to bring a lady-appropriate gift and gentlemen a man-appropriate gift - under $10 and gift-wrapped. If you did not sign up at the last meeting and plan to attend, please call Hanni Sigel at 826-1009. Let’s all come out and kick off the holiday season in style.

November Field Trip to Big Joe Canyon

At 8:30 am on Saturday November 15 ten members assembled in the Willcox Safeway parking lot, Bob explained the route we would follow and we headed east on I-10 to just across the New Mexico line. We took the first NM exit and then went south about 8 miles arriving at the mines in Big Joe Canyon at 10. Bob pointed out the honey calcite crystal vein on the hillside and the tailings that had various copper minerals. Most of the group headed for the calcite veins but after a few whacks at the very hard matrix surrounding the vein, most simply found pieces lying on the ground that someone else had broken out. But Henri was determined and persistent and after an hour or so, he had a very large piece of dark honey-colored calcite crystals. Some of the group went to another mine and tailings pile about ½ mile from the tunnels. Bob Fenner discovered two cute Ring-tailed Cats (one dead) that had gotten trapped in a cistern near the mine buildings. Bob and Don later found an old paint can and were able to put water in it for the surviving cat and an old board as a ladder/ramp. We found honey calcite crystals, popcorn aragonite, peacock ore, limonite, jasper, agate, chrysocola and druse. After everyone had found good specimens, Don declared the Club field trip over and most of the group dug out flashlights and headed into one of the tunnels finding more calcite crystals and aragonite in the tunnels along with some bats. Most of the group got back to Willcox about 4 and had 1950’s style burgers, fries and décor at Carter’s. We thank Bob and Barbara Fenner and Henri Van den Bos for arranging an excellent field trip to a very productive collecting site.

Lapidary and Silversmith

Classes

Lapidary classes are in session on Tuesday from 6:30 to 9:30 PM at the Lapidary Room behind the Fire Station. Show up or call Larry Strout at 826-3991. Larry is also available to teach silver soldering, a prerequisite to silver smithing. Keith McRobert will resume teaching silver smithing in early January. Call Don Hammer at 384-3105. Come and join the fun of lapidary, silversmith, and wire wrap lessons. Interested, any questions? Wire Wrap - call Larry Strout 826-3991.

    • Club Calendar:

December

8 Christmas Party

30 Board Meeting

January

12 General Meeting

24 Field Trip

29 Board Meeting

February

9 General Meeting

21 Field Trip

26 Board Meeting

March

9 General Meeting

14 Field Trip

April

2 Board Meeting

13 General Meeting

18 Field Trip

30 Board Meeting

May

11 General Meeting

16 Field Trip

21 Board Meeting

June

6 Club Picnic

Upcoming Regional Events

December

      1. El Paso Gem & Mineral Show featuring gems, minerals, fossils, beads, silver jewelry, tools, equipment, geode cutting, silent auction, demonstrations, door prizes and free parking. Hours 10 am to 6 pm. Contact Gem Center USA at 877-533-7153.
    • 9-11 Flagg Gem & Mineral Show, Mesa Community College. Hours – 9 am to 5 pm. Gems, minerals, fossils, lapidary material. Free parking and admission. For information Darrel Dodd 480-575-5214 or Ray Grant 480-814-9086
      1. Flatirons Mineral Club Annual Gem & Mineral Show. Boulder County Fairgrounds, Longmont, CO. Gem, mineral, jewelry and lapidary equipment, exhibits, demonstrations, speakers and classes. For information http://bcn.boulder.co.us/community/fmc/fmcshow.htm or call 303-438-8736.

January

    • 21-25 Quartzite Gem and Mineral Show. Gems, Minerals, Fossils and related hobbies. Daily field trips. For information powwow@qlaaz.org or www.qlaaz.org
    • 30 – Feb 15 The Tucson show http://www.tucsongemshowguide.com/
    • February
    • 27 – March 1 Denver Gem and Mineral Guild 2009 Show. Jefferson County Fairgrounds, Golden, CO. For information janiemube@comcast.net
    • 12-15 Deming Show. Jerry & Carolyn Abbey 575.546.4338
    • March
    • 12-15 Deming Show. Jerry Abbey 575.546.4338
    • 20-22 Albuquerque 40th Annual Gem & Mineral Show. Minerals, fossils, jewelry, beads. Hours 10 am to 6 pm. For information call Paul Hlava 505-255-5478.

Club Officers for 2008

President: Don Hammer 520 384-3105

V.President:Henri Van den Bos 520 384-0288

Secretary: Diane Brower 520 826-4672

Treasurer: Walter Sigel 520-826-1009

Delegate at Large: Jack Light520-384-4774

Hospitality Coord: Hanni Sigel 520-826-1009

Past President: Paul McKnight 520 824-4054

Calcite

Calcite, which gets its name from "chalix" the Greek word for lime, is a most common mineral, comprising about 4% by weight of the Earth's crust and is formed in many different geological environments. It forms oolitic, fossiliferous and massive limestones in sedimentary environments and even serves as the cements for many sandstones and shales. Calcite is a major component in the igneous rock called carbonatite and forms the major portion of many hydrothermal veins. With calcite so abundant and so widely distributed it is no wonder that it can be so varied. The crystals of calcite can form literally a thousand different shapes by combining the basic forms of the positive rhombohedron and negative rhombohedron and these forms can combine to produce the thousand different crystal variations. There are also phantoms, included crystals, color varieties, pseudomorphs and unique associations. There simply is no end to the varieties of calcite.

The most common form of calcite's varieties is the classic scalenohedron or "Dogtooth Spar". This variety appears as a double pyramid or dipyramid, but is actually a distinctly different form. The point of the scalenohedron is sharp and resembles the canine tooth of a dog, hence the name.

Calcite is the primary mineral component in cave formations. Stalactites and stalagmites, cave veils, cave pearls, "soda straws" and the many other different cave formations. It is the fact that calcite is readily dissolved that these formations occur. Another variety is the so called "Iceland Spar", which is basically clear cleaved fragments of completely colorless (ice-like) calcite. Most of today's iceland spar comes from Mexico. The iceland spar displays the classic cleavage form of calcite, the rhombohedron. Iceland spar is used for optical equipment and during World War II it was a strategic mineral as it was used for the sighting equipment of bombardiers and gunners. It is iceland spar that best demonstrates the unique property of calcite called double refraction. Double refraction occurs when a ray of light enters the crystal and due to calcite's unique optical properties, the ray is split into fast and slow beams. As these two beams exit the crystal they are bent into two different angles because the angle is affected by the speed of the beams. A person viewing into the crystal will see two images of everything. The best way to view the double refraction is by placing the crystal on a straight line or printed word (the result will be two lines or two words).

Fluorescence, phosphorescence, thermoluminescence and triboluminescence are other important properties of calcite. Although not all specimens demonstrate these properties, some do quite well and this is diagnostic in some cases.

Calcite will always effervesce (bubble) when even cold weak acids are placed on specimens. The reason for the bubbling is in the formula:

CaCO3 + 2H(+1) -------> Ca(+2) + H2O + CO2 (a gas)

The carbon dioxide gas (CO2) is given off as bubbles and the calcium dissolves in the residual water. Any acid, just about, can produce these results, but dilute hydrochloric acid or vinegar are the two recommended acids for this test. Many sea organisms such as corals, algae and diatoms make their shells out of calcite by extracting carbon dioxide from sea water. Calcite is not the only calcium carbonate mineral. There are no less than three minerals or phases of CaCO3. Aragonite and vaterite are polymorphs (latin for "many shapes") with calcite, meaning they all have the same chemistry, but different crystal structures and symmetries. Aragonite is orthorhombic, vaterite is hexagonal and calcite is trigonal. Aragonite is a common mineral, but is vastly out distanced by calcite which is the more stable mineral at most temperatures and pressures and in most environments. Vaterite on the other hand is extremely scarce and rarely seen. Aragonite will over time convert to calcite and calcite pseudomorphs after aragonite are not uncommon.

SUNSITES GEM AND MINERAL CLUB

P.O. Box 87

Pearce, AZ 85625