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Rainbow CalSilica - Mexico
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Rainbow Cal Silica cab 10/25/11 - 01 - Big, Pendant sized, Super Nice, High Dome, Designer Marquis Gem Cab!
x 20 x 7.4 mm - 42 carat - $45.00

Rainbow Cal Silica cab from Mexico
This material is a new discovery from Mexico and has many layers of different colors: red, brown, green, tan, blue, yellow, white and others. It has been verified as a natural stone not man made. It is composed of Calcite-Allophane (Blue and green) and silica with various trace metals that cause the other colors. It has been stabilized the same as Turquoise. This makes it very stable and easy to cut and polish. Be the first on your block to have some of this unique stone. There is a big controversy of whether this stone is natural or man made. Here is what I know:
The original Geologist who did a scanning electron microprobe study of an untreated piece with rhyolite matrix attached, maintains that it is a natural stone and he could not detect anything that would suggest this is man made. GIA has published an article in Gems and Gemology stating that they tested a treated piece obtained in France, using Raman Laser Spectroscopy and it was found that the blue and yellow colors matched a man made pigment. They also said it had polymer and a paraffin-like substance. Since this article the source has sent treated and untreated samples as well a piece of the acrylic they use to stabilize it, to a Geologist/Chemist at a University Back East and he has faxed them his preliminary findings which I saw today and they clearly show that the blue and yellow does not match any man made pigments and no traces of paraffin were found. I will continue to post updates on my webs@%$ (see my "about me" page) as I know more and will obtain a copy of this report very soon. I cannot guarantee this is a natural stone since I am not an expert, but it is now looking like the GIA testing was incorrect at best and there is no solid evidence that it is man made and much evidence that it is natural. If it is man made, it's one of the best yet. The stone is beautiful and I like it whether if it is natural or not.