ruby1

Most of us know that not every red gemstone is a ruby.  Garnets, tourmaline, and even diamonds can be red.  But if you are in the market for a ruby, know that many substitutes exist.  I recently put on a seminar about rubies, their imitations, and synthetics.  Let me share three pieces of advice on buying a ruby.

1) Buy it from an A.G.S. member store. Only jewelry stores who adhere to the strict consumer protection standards of the American Gem Society  will have the A.G.S. sign by the front door.  These stores are required to be informed on ethical issues and questionable practices facing the gemstone and jewelry industry.  At least one employee of the store must be a registered jeweler, which requires yearly testing to renew the designation.

American Gem Society

2)  Look at that beautiful stone under the microscope.  All A.G.S. member stores are required to have a microscope at their store.  Ask to look at the piece you’re considering.  If the stone shows some inclusions under magnification, especially whitish or colorless rounded crystals or a lacy-looking fingerprint, that’s a good sign.   Be suspicious of a stone that looks perfect under magnification.  Natural rubies generally have inclusions.  Remember to ask about treatments on the stone.  Most rubies have been heat-treated to improve their color and sometimes their clarity.  Heat treatment is permanent and does not affect the durability of the stone.  If the stone has fractures that have been lead glass-filled to enhance the clarity, it is not as valuable as one that has not. In fact, most gemologists feel that these “composite rubies” shouldn’t even be called rubies because so much of their weight is due to the lead-glass.  Be aware that a glass-filled stone is not durable and should never be subjected to heat or an ultrasonic cleaner.

3) Don’t assume that, because it’s old, it’s real.  Synthetic rubies have been produced since the early 1900s.  Rubies were also imitated using glass, assembled stones of garnet and glass, and other natural red stones like spinel.  Even the “Black Prince’s Ruby” in the British Imperial Crown is actually a 170 carat red spinel!

British Imperial Crown with the "Black Prince's Ruby"

British Imperial Crown with the “Black Prince’s Ruby”