Joined: Tue Dec 06, 2005 11:45 am Posts: 1107 Location: Cape Elizabeth, Maine
I know glass is commonly used as a Tanzanite imitation, along with synthetic fosterite. I know some people try to sell cordiertite (iolite) as tanzanite. Are there any other imitations on the market?
I had another EBay buyer come in this week with a pendant, a ring, and a pair of earrings that were sold to her as"tanzanite". Upon doing a gem identification for her, I quickly determined that none of the stones were tanzanite - but I couldn't determine the exact material.
They were all singly refractive, one of the stones showed strong ADR, so of course none of them showed pleochhroism (although two of them looked like they had some red flashes to the human eye - but not under the dicroscope). They had no inclusions that would identify them, but the thing that threw me was the RI on all of them - they were all OTL and the RI's were spread between 1.81 - 2.15 which rules out glass.
Are G.G.G., YAG, and CZ being made to look like tanzanite these days?
Of course the seller had a "no return" policy and the buyer knew just enough about gemology to be dangerous. Whenever my clients tell me they've purchased something on EBay and they want me to ID it or appraise it, I brace myself because I know I will probably have to deliver the bad news. So far every EBay purchase I have seen in my store has been misrepresented.
Joined: Sun Oct 16, 2005 4:09 pm Posts: 140 Location: Oregon
Sniz! I think I have seen YAG on JTV that the show hosts were refering to as Tanzanite colored... or a tanzanite "like" color.
And other shopping channels have been selling tanzanite simulents in jewelry, not sure what material it was though.
_________________ And despite all my rage, I am still just a rat in a cage.
Some manufacturers have grown a bluish purple synthetic yttrium aluminum garnet (YAG) that mimics tanzanite’s color. One version goes under the trade name Tanavyte. The material is singly refractive and over the limits of a standard refractometer, with an RI of 1.80 or higher. Because it is singly refractive there is no pleochroism, an important distinction. With the polariscope, it might show anomalous double refraction resulting from strain within the crystal .
Users browsing this forum: No registered users and 10 guests
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum