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Wednesday, January 27, 2010

SLAB CUTTING - which way makes a difference !

First I want to thank Ron at theimage1.com for his great pictures and reports from Quartzite.
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One of his great photos shows dramatically the difference one can get when slicing slabs for Cabbing or Pendants out of the same stone/rock. As marked on the picture, the top slab was cut along the seam of the rock, where the second picture was cut across or thru the seam. Two dramatic different results and patterns from the same rock.


So as you can see, before placing that stone/rock on the cutting saw, look it over carefully and try, if possible, to determine where the seam is, if one present, and then cut depending on what kind of pattern you want from that particular piece of material. Chances are, it won't look like the same material when finished. And yes, the figures marked on the stones in the picture, is the cost on those two slab slices.
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Picture from Ron, at theimage1.com.
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Sunday, January 24, 2010

TUCSON GEM FAIR 2010 !

Well the big one is here ! Yep, at the end of this week Tucson Gem Fair 2010 gets under way. Something for everyone -- gemstones - beads - minerals - fossils - you name it and if it is related in any way to gems, minerals or fossils, you can probably find it at one of the more than 40 shows that take palce over the next 3 weeks.
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One can be overwelmed by the amount of gems and beads present.
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Please bear with us for the next several weeks as we may not be able to update the web-site until return and get everything identified and catalogued. If you try calling, we have found in the past that cell-phones do not always get a good signal inside the metal buildings, so please wait a bit and try again at a later time.
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If you want to check on a particular show, or see if your favorite Vendor is present, check out the Tucson Show Guide at http://www.colored-stone.com/tsg/.
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Sunday, January 17, 2010

COLORED STONE MAGAZINE is No More !

After 22 years Colored Stone Magazine has ceased publication. Other than a letter addressed to advertisers and signed by V.P. David Pyle, the parent company, Aspire Media, publicly known as Interweave Press, there has been little by way of an epitaph. The website is still up. Subscribers who have recently signed up have been told that they will be provided with an alternate subscription. The website is no longer accepting subscriptions requests.
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With the demise several years ago of Gem Key, the loss of the 22 year old magazine leaves only two publications, one a relative new comer, In Color, published by The International Colored Stone Association and Gem Market News, another quarterly published by The Guide, covering the colored gemstone industry.
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Founded in 1987 by the Gilbert family as a quarterly industry news magazine, Colored Stone has been through several incarnations. Its current owner, Interweave Press, is its third. As the name suggests, the parent company is most involved in publishing consumer oriented fiber arts magazines.
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What brought the magazine to its end? According to Pyle’s letter it was all about the current economic situation. “The corporation was definitely profit driven” said Morgan Beard the former editor in chief. Beard who ran the magazine for 10 years, notes that “Colored Stone never really made money. The Tucson Show Guide kept the magazine afloat.” At its peak, the circulation was between 8-10,000, “sometimes”, she said, “we broke even.”
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“Sorry to see it go”, said dealer Bear Williams summarizing industry reaction. “Yes, it’s too bad”, said Simon Watt (Mayer & Watt), but Watt goes on to make the broader point that: “we never have had any sort of real industry journalism.”
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Many readers will recall Colored Stone’s controversial coverage of the so-called “Copper Diffusion” issue by then Editor-in-chief David Federman. Federman wrote several articles based unsupported claims by the proprietor of an unaccredited online gemological school concerning copper diffusion treatment of tourmaline, garnet and topaz. “Federman was on the right track with his coverage of enhancement issues”, but, on the James issue, “I called and told him, ‘“David you have lost perspective, he hung up on me.”’ “David Federman is a great writer but a lousy editor.” said Watt. Beard agrees, “Federman wrote what he believed but often did not investigate or take a balanced approach”, she said. Eventually the claims were determined to be faulty by Colored Stone’s own Science Editor among many others.
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Federman’s coverage also resulted in a lawsuit by the Direct Shopping Network (DSN) that named Colored Stone and Interweave Press as defendants. Did the controversy contribute to Interweave’s decision to pull the plug on Colored Stone? Beard doubts it. “Interweave just shut down three of its magazines. I think they finally decided, we have the Show Guide making money and the magazine not, so why continue the magazine?” she speculated. Another source told me that an outside executive had been brought in to reorganize the magazine.
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Another Interweave publication, the venerable Lapidary Journal/Jewelry Artist may be asked to step up and fill in the gap caused by the demise of her sister publication. Originally called just Lapidary Journal, the 60 year old magazine changed its focus just two years ago and directed its coverage more toward jewelry, but since October has begun repositioning itself back into the gem world said Merle White, Editor-in-Chief. When asked if this meant that her magazine would pick up the slack left by Colored Stone, “that has not been discussed”, she said. “We strengthened our gem coverage because our readers asked for it” she stated. Federman was terminated but Managing Editor, Karla Rosenbusch has been retained to coordinate The Tucson Show Guide. What will be the fate of Colored Stone’s online newsletter Gem-Mail? “That is under discussion” said White.
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Reprint from Gem-Wise and also posted on Saturday, January 16th, 2010 at 2:03 pm and is filed under David Federman, International School of Gemology, Robert James, Uncategorized
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Saturday, January 16, 2010

MARCASITE - a Jewelry Trade Name misnomer !

The mineral Marcasite, many times called "white iron Pyrite" or "fools gold", is iron sulfide. Though Marcasite has the same chemical formula as Pyrite, it is a polymorph of Pyrite and crystalizes in a different crystal system, thereby making it a totally separate mineral. Marcasite (picture to right) is often mistakenly confused with Pyrite (picture below) but Marcasite is lighter and more brittle. Specimens of Marcasite often crumble and break up due to the unstable crystal structure, and it is this crystal structure that is the main difference between Marcasite and Pyrite.
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Marcasite can be formed as both a primary or a secondary mineral. As a primary mineral it forms nodules, concretions and crystals in a variety of sedimentary rock, where it forms as sharp individual crystals and crystal groups. As a secondary mineral it forms by chemical alteration of a primary mineral such as Chalcopyrite. On fresh surfaces it is pale yellow to almost white and has a bright metallic luster. It tarnishes to a yellowish or brownish color and gives a black streak. It is a brittle material that cannot be scratched with a knife.
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Marcasite may go through a condition known as "Pyrite decay", in which a specimen slowly disintegrates into a white powder. When a specimen goes through pyrite decay, the marcasite reacts with moisture in the air, the sulfur combining with water to produce sulfuric acid that attacks other sulfide minerals. It is unsafe to have around at this point.
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The Marcasite/Pyrite polymorph pair is probably the most famous polymorph pair next to the Diamond/Graphite pair. Adding to the confusion between Marcasite and Pyrite is the use of the word "Marcasite" as a 'Jewelry Trade Name'. The term is applied to small polished and faceted stones, usually Pyrite that are inlayed in sterling silver and sometime platenium with black rhodium highlighting the stones. But even though the jewelry trade refers to these small stones as "Marcasite", they are actually small pieces of Pyrite. In jewelry, Pyrite is used as the gemstone and is improperly termed "Marcasite" following the misnomer of the trade name. True Marcasite is never used as a gemstone in settings due to its brittle and chemically unstable structure.
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Pendants of Sterling Silver with "Marcasite (Pyrite)" stones as highlights
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For collectors pieces of Marcasite are prized in a collection. But they must be kept sealed in air tight containers so that they do not break down and become a pile of white powder. Miners, however, often viewed Pyrite and Marcasite negatively since they had a deceptive appearance, which many mistook for gold. Many based their opinions on where to dig or pan based on pieces of these minerals being in the ground or water, and too late learned that these stones were worthless. Thusly they inherited the name "fool’s gold".
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Wednesday, January 13, 2010

RUBY - be careful when buying at Tucson !

Ruby Treatments - Flux Fracture Treated Ruby
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In a general alert to the gemological community, Stone Group Labs, LLC and Deljanin & Simic Gemological Service Inc. have submitted a "Gem Watch" alert for Ruby treatments. Please note that this is not the same treatment as that of the lead glass type filling. This process is a progression on earlier heat treatment chemical formulas typically used on Mong Hsu Ruby but is a multi-step cleaning and fracture filling process involving extensive flux healing. Any buyers of this material will want to ask the right questions, and wholesalers should be expected to have the right answers.
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This treatment is typically being performed on Mozambique and Madagascar Ruby mined in certain locales, but rough sources could vary. The picture shows a before and after of such treatment. The starting material is often that of a marble like host where the rough is first acid bathed to clean and remove the typical various inclusions and intergrowth. There is usually enough of the lamellar twinning and basal parting planes that require the acid cleaning, and at the same time facilitate the massive introduction of the fluxes, with some additional elements. .
Left: rough before treatment -- Right: after treatment but before cutting and polishing
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While the two laboratories are still investigating the full nature of the chemistry of the treatments, with the assistance of the AGTA, they all see the current need to issue this notice in time for the upcoming 2010 Tucson Gem Show. This material is already being sent to the various labs for identification. It is a lot more difficult to detect than the lead glass filled rubies. It is suggested that jewelers and gemologists examine very closely any Ruby over 3 ct, especially any with surface reaching fractures. More studies are being conducted with additional samples to completely characterise these stones, and come up with proper identification codes and nomenclature for use during the 2010 Tucson show so that this new product will be properly disclosed.
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Monday, January 4, 2010

QUARTZSITE - A major prelude to Tucson 2010 !

Welcome to QUARTZSITE and Desert Gardens on the California - Arizona State Line.
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2010 Calendar of Events
January 01 - February 28, 2010 Desert Gardens-Gem & Mineral Show
January 01 - January 10, 2010 Tyson Wells Rock & Gem Show
January 09 - February 24, 2010 Main Event
January 15 - January 24, 2010 Tyson Wells Sell-A-Rama
January 16 - January 24, 2010 Sports, Vacation & RV Show
January 27 - January 31. 2010 Hobby Craft & Gem Show
January 29 - February 7, 2010 Tyson Wells Arts & Craft Fair
January 20 - January 24, 2010 Annual Pow Wow
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Then it is on to the Tucson Gem Fair 2010 during February !
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When its clear it is beautiful, but then the wind and sand rolls in.
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but the Show goes on, and the weather clears again.

There is plenty to see, masses of rock and minerals all over the place, inside and out.

Tables of new material, like Imperial Sarah Jasper,

or buckets of everything and anything imaginable,

and hugh slabs of Tigereye and TigerIron,
or maybe even some unknown wierd stuff.
How about a Geode big enough to stand or sit in
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and a few odd things also.
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Whatever you want, you could probably find it at QUARTZSITE and for sure at the following Tucson Gem Fair 2010. Many of the vendors at QUARTZSITE will move to Tucson as the various different shows open up there during the month of February.
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Pictures thanks to Ron, theimage1 and Quartzite.com.
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Saturday, January 2, 2010

MOLDAVITE - The Cosmic Connection !

Moldavite or in the Czech language 'Vltavin', is an olive-green or dull black greenish vitreous substance assumed formed by a meteorite impact. It is a one kind of tektite. It was named for the town of Moldauthein in Bohemia in the Czech Republic, where it occurs. Most figure that about 15-20 million years ago a meterorite shower fell in the Moldau Valley of Czechoslovakia. The result of this shower was Moldavite, a rare crystal of a bottle-green, translucent hue. Although some people believe that it is a true meteorite substance (formed in outer space), it is more generally accepted that it originates from rock that was struck by a meteorite and melted thus forming the tektite or glass-like substance. According to this latter belief, moldavite then combines extraterrestrial and terrestrial properties.
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The total amount of Moldavite scattered around the world is estimated at 275 tons. There were only four moldavite mines in full operation in the Czech Republic, but those have now been closed according to the latest reports, and no more Moldavite is allowed out of the country. It was predicted in 2001 that in less than ten years Moldavite mining would come to an end. After this time, there will be virtually no appreciable amount of gem-grade Moldavite left in the ground. But that prediction was overcome by politics.
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There are typically two grades of moldavite: high quality, often referred to as museum grade, and regular grade. Museum and regular grade moldavite can be told apart by the way they look:

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Regular grade pieces are usually darker and more saturated in their green colour, and the surface is seen as closely spaced pitting or weathering. This type sometimes appears to have been broken apart from a larger chunk.

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Museum grade has a distinct fern-like pattern and is much more translucent than the regular grade. There is usually a fairly big difference in the price between the two. The museum grade "flower bursts" are much more prized by the connoisseur.






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High-quality moldavite stones are often used in hand-crafted jewelry and thus enter the market away from mainstream jewelry fashions. Most of the time, since not easy to facet, Moldavite is left in in 'raw' form and is wire-wrapped. But some better pieces can be faceted and make into beautiful pieces.

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Being hard like glass, rings are a common jewelry piece.