Opals are unique gems with their own unique terminology. Learn the modern standard system for classifying and appraising opals used by major gem labs.
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Opal Stones and Gems: Value, Price, and Jewelry Information
Opals are in a class by themselves. As a species, opal is so unique it has its own descriptive vocabulary....
Gemstone Doublets, Triplets, and Other Assembled Stones
Made from two or more materials, assembled gems can make durable and affordable jewelry. Learn more about gemstone doublets, triplets,...
Tips for Cabbing and Carving Opals
Opal cabochons can fetch high prices but may be difficult to cut. These tips for carving opals can help gem...
An Interview with Opal Expert Joel Ragan
Opal expert Joel Ragan has worked with these gems for 45 years. Learn how he got started and his top...
Gemology Book Reviews: Careers
Learn how varied gemology careers can be. Our gemology book reviews highlight three different approaches — as art, science, and...
Augelite Value, Price, and Jewelry Information
Soft and brittle, rare augelites are difficult to cut and unsuitable for wear. Faceted transparent pieces are only found in...
Six Famous Aquamarines
Aquamarines have been cut into many large and beautiful gemstones. Let’s take a look at six of the world’s most...
Risk Management and Gem Buying for Profit
You can’t eliminate all risks from gem investing, but understanding the risks you’ll face and your appetite for them will...
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