Gas Bubbles
Most, but not all, of the composite "rubies" I have examined have contained gas bubbles. The classic look of a gas bubble is a bright sphere within a sphere. These can be tiny or large, individual or clouds of bubbles (G, H, J). Gas bubbles are in the glass and not the corundum (ruby) part of the stone. Gas bubbles do not occur "free floating" in ruby or sapphire.
The illustrations below show the damage occurring to composite "rubies" in jeweler’s pickle of an hour and half. The damage to illustration K was visible to the naked eye within 30 seconds of immersion into the pickle. Illustration L was exposed to fresh lemon juice for 48 hours and then lightly heated with torch.
This brief article is an introduction to three of the easiest ways to identify composite "ruby." If you suspect you have been sold a composite or glass filled "ruby," please contact AGA or use the AGA Consumer Complaint form.
(i) From gemstone.org, the website of the International Colored Gemstone Association
MUS Price at posting:
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