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Composite Ruby - Lead glass treated Ruby
https://gemologyonline.com/Forum/phpBB2/viewtopic.php?f=69&t=13453
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Author:  Craig Lynch [ Sat Mar 12, 2011 4:06 pm ]
Post subject:  Re: Composite Ruby - Lead glass treated Ruby

The question is not about the labs and others identifying LGFR/composite ruby early on, and not really about greed although it is absolutely true that greed is the gas in the engine here. I'm truly wondering why no one has seriously questioned it's title of "ruby" right from the gate 7 years ago. I think the Labs did what they were suppose to do nearly from the start, they may have been a little late in seeing the complete instability (my opinion) of the material, but other than that they were right on. The chemistry is there, (although a copious amounts of additional chemistry Pb-glass, has been added too) the basic "un-heated" inclusions are there when not hidden by the glass, the RI is there, the hardness is there in spots :). So in simple terms it mostly quacks like duck, yet is it ruby? It is corundum mixed with copious amounts of Pb glass, The finished product does resemble ruby in color (largely because of the glass). But when it starts out as purple brown reddish corundum rock which is acid treated to remove all other material leaving just the corundum which then infused with high RI Pb glass (commonly 10% to 30% or more, by weight) so it can then stable enough to be cut and polished. How can it really be called Ruby? Its kind of like "The Emperor New Clothes" story. I'm not looking to blame anyone or any organization or Labs. But perhaps this has reveled a blind spot in our industry.

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