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July 2008
Juniors will show off their displays and the awards they received * Ice Cream Social * Bring your favorite topping
Party Time….. Apple Pie Bake-off and maybe a surprise. * Auction * Imagine what you might need for your own workshop
San Diego Lapidary Society Annual Rock, Gem, Mineral and Jewelry Show September 6th and 7th 2008 Show Dates: 2-6--MADRAS, OREGON: Show, "Fourth of July Pow Wow"; All American Rock & Gem Pow Wow Club of America; Jefferson County Fairgrounds; ; camping, daily field trips, dig for agate, jasper, thunder eggs, petrified wood for a fee, bring rockhounding tools, kids' rock toss/scramble, Country Kitchen, guest speakers, music, auction, bingo, door prizes, more than 75 vendors, rough rock, finished jewelry, equipment; contact Rocky McCall, 8330 272nd NW, Stanwood, WA 98292, (360) 629-2515; e-mail: rm711@tgi.net 3-6--SISTERS, OREGON: 12th annual show, "Sisters Round-up of Gems"; Jean Miller; Sisters Elementary School, 611 E. Cascade, off Hwy. 20; Thu. 9-6, Fri. 9-6, Sat. 9-6, Sun. 9-4; free admission; donations benefit Oregon National Guard Families Emergency Fund; contact Jean Miller, P.O. Box 136, Molalla, OR 97038, (503) 829-2680; e-mail: shadow92337@netscape.com; Web site: www. ogmshows.com 18-20--REEDSPORT, OREGON: Show, "Lower Umpqua Gem & Lapidary Show"; Lower Umpqua Gem & Lapidary Society; Reedsport Community Bldg., 415 Winchester Ave.; Fri. 10-6, Sat. 10-6, Sun. 10-4; free admission; dealers, demonstrators, silent auction, spin the wheel, door prizes, displays, raffle; contact Bill Hendrickson, 100 Riverbend Rd. #17, Reedsport, OR 97467, (541) 271-6816; e-mail: bamoonman7@msn.com 25-27--GRESHAM, ORGEON: 2nd annual show, "Gresham Gem, Mineral, Jewelry Show"; Jean Miller; Mount Hood Community College, 26000 S.E. Stark, enter off Kane Rd., parking lot A; Fri. 10-6, Sat. 10-6, Sun. 10-4; ugly jewelry contest, donations requested for Oregon National Guards families Emergency Fund; contact Jean Miller, P.O. Box 136, Molalla, OR 97038, (503) 829-2680; e-mail: shadow92337@netscape.com; Web site: www.ogmshows.com JULY-AUGUST 2008: 31-3--SPRUCE PINE, NORTH CAROLINA: 51st annual show, "North Carolina Mineral and Gem Festival"; Mitchell County Chamber of Commerce; Pinebridge Coliseum, 97 Pinebridge Ave.; Thu. 10-6, Fri. 10-6, Sat. 10-6, Sun. 12:30-5; adults $3, seniors $1, children under 5 free; retail and wholesale vendors, exhibits, mine tours; contact Patti Jensen, P.O. Box 858, Spruce Pine, NC 28777, (828) 765-9033; e-mail: pjensen@mitchell-county.com; Web site: www.mitchell-county.com AUGUST 2008: 1-3--NIPOMO, CALIFORNIA: Show, "Rainbow of Gems"; Wes Lingerfelt; St. Joseph's Church; 298 S. Thompson Ave.; Fri. 10-5, Sat. 10-5, Sun. 10-5; free admission; raffles, prizes; contact Wes Lingerfelt, 110 W. Bennentt St., Nipomo, CA 93444, (805) 929-3788; e-mail: Rocks4u@prodigy.net; website: Web site: www.omsinc.org 1-3--PRESCOTT, ARIZONA: Show and sale; Prescott Gem & Mineral Club; Embry-Riddle Aeronautical University Activity Center, 3700 Willow Creek Rd.; Fri. 9-5, Sat. 9-5, Sun. 9-4; adults $2, children 12 and under free with paid adult; dealers, fine jewelry, beading components, mineral specimens, tools, lapidary equipment and rough, door prizes; contact Larry Jackson, P.O. Box 3923, Chino Valley, AZ 86323, (928) 636-9188; e-mail: lpjack65@cableone.net; Web site: www.prescottgemmineral.org 2-3--SAN FRANCISCO, CALIFORNIA: 54th annual show, "Golden Gateway to Gems"; San Francisco Gem & Mineral Society; San Francisco County Fair Bldg., 9th Ave. at Lincoln Way; Sat. 10-6, Sun. 10-5; adults $6, seniors and students $5, children under 12 free; displays, demonstrations, gems, jewelry, minerals, lapidary rough, fossils, lectures; contact Ellen Nott, (415) 564-4230 9-10--LAKEVIEW, OREGON: Show, "Tallman Rock Round-up"; Tallman Rockchippers; Lake County Fairgrounds, N. 4th St.; Sat. 10-5, Sun. 10-4:30; field trips (Oregon sunstone, etc.), dealers, demonstrations, children's activities, silent auction; contact Johanne Diedrich, Hi Desert Craft Rock Shop, (541) 947-3237, or LeRoy Johnson, 39 N. L St., Lakeview, OR 97630, (541) 947-4267; e-mail: lostmymarblesoregon@yahoo.com
by Andrew A. Sicree The necessity of minerals For every human being on Earth there is a hole in the ground and that hole is a mine. Although few of us think about it, every physical object we own or use in modern life starts out in either plant or animal, or “mineral,” form. Plant and animal products are harvested from farms, forests, or the sea. But everything else must come out of that hole in the ground. In the economic world, the term “mineral” is much broader in meaning than its strictly mineralogical definition. In other words, the mineral industries include aggregate mining, oil and gas drilling, coal mining, cement making, tombstone quarrying, etc. Oil, coal, methane, and limestone, granite, and other rocks, are thus “minerals.” Your personal mine The size of your personal mine depends upon your lifestyle. In 2007, the average American needed more than 46,000 pounds of minerals to support their lifestyle. Over the course of a lifetime, the average American will require about 3,600,000 pounds of minerals. That is a hole approximately 40 feet deep by 40 feet wide by 40 feet across for every man, woman, and child in the country. Multiply that by the population of more than 300 million people and you can see why mining is important – it keeps our country going! How do we derive these numbers? Every year, the Minerals Information Institute (MII) in Denver, Colorado, uses data provided by the U.S. Geological Survey and the National Mining Association to determine how much of each commodity such as coal, oil, limestone, cement, natural gas, copper, gold, silver, etc., is being consumed nationwide. The annual amount consumed (for all rocks and minerals) is divided by the total population to determine the annual pounds used per American. Taking the estimated life expectancy (about 77.9 years in 2007) of Americans, the MII then calculates the total pounds of minerals needed to support each American throughout his or her lifetime. Amounts of minerals you use Using this method, one can determine the average amounts of individual mineral commodities (such as copper, cement, or coal) needed by a typical American as well as the sum total amount of all mineral products. Here are some of the lifetime amounts of various minerals needed for each American:
It is interesting to note that a similar analysis shows that the average American uses 1.57 troy ounces of gold during his or her lifetime. Stone, sand, and gravel make up the bulk of the tonnage. This is because of the huge quantities of rock needed in road construction and the foundations of buildings. Fuels (coal, natural gas, and petroleum) and industrial minerals such as clay, salt, and phosphate rock (used in fertilizer) make up another large portion. The minerals that produce lead, copper, zinc, iron, and aluminum, while lower in tonnage, are still very important for modern life. It is important to note that these numbers say little about the actual amounts of rock that must be moved to produce each pound of metal. For instance, if a copper mine exploits an ore that is 0.1% copper, one must mine 1000 pounds of waste rock for each pound of copper produced. The economic minerals There may be more than 4,000 known species of minerals, but we rely upon a relatively small number of “economic minerals” to produce commodities such as copper, fluorine, gold, aluminum, lead, zinc, etc. Sphalerite (zinc sulfide, ZnS) is the primary ore mineral for zinc. Gold is mostly recovered in the form of native gold although gold telluride minerals such as calaverite are important in a few mining districts (such as Cripple Creek, Colorado). Chalcopyrite (copper iron sulfide, CuFeS2) is a primary ore mineral for copper, although other minerals, such as bornite and malachite, may also contribute to production at some mines. The primary ore mineral for lead is galena (lead sulfide, PbS). There is an entire field within the mineral sciences called “economic geology” which involves the study of economically-important minerals and their origins. Most mineral species have little to no economic importance, although they still may have value to scientists and mineral collectors. The economic minerals, however, are valuable precisely because they are crucially important to modern society. ©2008, Andrew A. Sicree, Ph.D. The Importance of Polymorphism Three important rock-forming minerals share exactly the same chemical composition: Al2SiO5. These three aluminosilicate minerals are andalusite, kyanite, and sillimanite, and they are polymorphs. Kyanite belongs to the triclinic crystal system, while sillimanite and andalusite are orthorhombic (they have different “space groups” – meaning that the atoms, although the same, are arranged slightly differently). These three minerals are of interest to petrologists (guys who study rocks) because they can be found in many aluminum-containing metamorphic rocks. The particular Al2SiO5 species present tells us something about the degree of metamorphism to which the rocks have been subjected. For example, kyanite tends to form in metamorphic rocks that have been subjected to great pressures Buried at great depths, rocks feel pressure of about 1000 times atmospheric pressure for each 2 miles of burial depth (thus rocks at 20 miles down feel pressures of about 5000 atmospheres). Sillimanite, on the other hand, tends to form at temperatures above 500°C. You may hear a geologist talk about the “sillimanite zone” or “kyanite zone.” This is because kyanite, sillimanite and andalusite can be used as index minerals to the grade of metamorphism. Kyanite, sillimanite and andalusite are relatively common minerals and are easy to recognize in hand specimens. Thus, a field geologist can walk across a region of metamorphic rocks and examine rocks for the presence of index minerals. When our geologist passes from rocks that contain kyanite to rocks that contain sillimanite, he knows that he has passed from the “kyanite zone” to the “sillimanite zone” and that the rocks have been heated to more than 500°C. Boundaries between these zones can plotted on a geological map and are referred to as isograds (lines of the “same grade”). ©2008, Andrew A. Sicree, Ph.D. The Simple Flame Test The widespread use of x-ray diffraction and electronic elemental analytical equipment may lead one to believe that you can’t do mineralogy without a lot of very expensive equipment. But famous mineralogists such as James Dwight Dana did their work long before the days in which fancy XRF (x-ray fluorescence) units became available. They used their eyes, noses, and some simple apparatus to conduct tests and make observations about minerals. One simple test that you can easily do at home is the flame test. Essentially, the flame test involves holding a small sample of a mineral in a flame and observing any colors produced. The color produced can be related to the composition of the mineral. For instance, in the flame, copper minerals will produce blue or green colors. Classically, flame tests involve use of an alcohol lamp, a blowpipe, and a platinum loop to hold the mineral sample. This equipment can be purchased from some mineralogical supply houses, but you can do a simple version of the flame test using cheaply-acquired common equipment. To get started performing simple flame tests all you need are some sets of cheap tweezers, a dropper bottle of 10% hydrochloric acid, some small plastic pans, and a propane torch. You can use your rock hammer to crush small samples of minerals to be tested. Begin by selecting a mineral that you know will produce a strongly-colored flame. A sample of malachite or azurite, or strontianite or celestine, will work well for practice and for demonstrations. After you have practiced with a known mineral, you can attempt flame tests with unknowns. Ignite your propane torch and set it upright in the center of a sturdy table where it cannot be knocked over. Adjust the flame to obtain a one- to two-inch long cone of flame. If the flame is highly colored, chances are good that the flame is too long or that the nozzle is contaminated – you may need to buy a new nozzle. Crush a pea-sized piece of the mineral into a pile of small chips and powder. Then put the powder in a plastic pan. Put a drop of the acid solution in the pan as well next to the pile of powder. Use a clean tweezers to pick up a small chip of mineral, dip it in the acid, and then rub the dampened mineral in the mineral’s powder. Note any reactions (carbonate minerals will fizz, for example). Now insert the tweezers tips into the flame of the propane torch. You will have to move the tips into the center of the flame (experiment to find the best spot). The flame will be colored briefly (for a few seconds at most) so note the color. Don’t leave the tweezers in the flame too long or they will begin to conduct heat back to your fingers. After using the tweezers clean them using a small of acid, and rinse them well with water. This method is not quite the same as the method used when you employ a proper platinum wire loop to hold the tested mineral. Platinum will not react with the acid and the flame. Cheap tweezers will corrode at the tips after use. Cleaning them will help prolong their usefulness. Minerals such as barite, malachite, azurite, celestine, and strontianite can all be used in flame tests. For instance, strontianite contains strontium, which gives a crimson color in the flame. The flame test can be used to differentiate strontianite from calcite (both of which will “fizz” in contact with acid. You can find tables of elements and their flame test colors in many mineralogy texts. Another good candidate for flame test demos is the salt substitute sold in your local grocery store. Salt substitutes contain potassium chloride (sylvite) rather than sodium chloride (halite). The substitutes taste the same but are purchased by health-conscious shoppers because they contain no sodium. Salt substitutes provide a cheap way to demonstrate the lavender color of a potassium-tinged flame. Note that sodium produces a strong yellow flame – so strong that when it is present it tends to over-power any other colors produced by other elements. You can test salt substitutes for the presence of sodium: if you see the lavender flame, there is very little to no sodium present. Dr. Andrew A. Sicree is a professional mineralogist and geochemist residing in Boalsburg, PA. This Popular Mineralogy newsletter supplement may not be copied in part or full without express permission of Andrew Sicree. Write P. O. Box 10664, State College PA 16805 (814) 867-6263 or email sicree@verizon.net for more info. ©2008, Andrew A. Sicree, Ph.D.
Skillfully merging art and science, a variety of techniques are used to help gemstones reach their full potential. As critical as good cutting, enhancements and treatments are an integral part of the modern gemstone industry. With its roots in antiquity (e.g., heat treatment has been practiced in India for over 4,000 years), most of the techniques used simply facilitate the beautiful end results of the earth's natural processes. Below are some answers to common gemstone enhancement, treatment and care questions. Is the use of enhancements and treatments globally accepted? As long as they are disclosed, all permanent enhancements and treatments are globally accepted. As the majority of gemstones traded internationally have undergone some form of enhancement, always assume treatments when purchasing gemstones. Do enhancements or treatments affect a gem's value? For some varieties there is no difference between the values of enhanced, treated or natural gemstones. However, high quality unheated Rubies and Sapphires are extremely rare and command a much higher market price. When purchasing Rubies and Sapphires, please be aware that unheated/untreated specimens are almost non-existent, and as a result, always purchase from a reliable source or have the seller's claim verified by a gemologist. The following table shows the enhancements and treatments used for some popular gemstones, their purpose, frequency and care. A several part addition to Shop Notes & News. (This is several pages. One section will be added in future editions of Shop Notes & News)
Cave Minerals
LAST MONTH’S SOLUTION - Some Long Words
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