Hybrid Gemstones
Some treatments add lab-created material to mined gemstones. The part-natural, part-synthetic nature of these gems has prompted some in the…
Hot Point Testing
Step 3: Practical Gemology Lesson 21 Back to syllabus Hot point testing can determine if some gem materials are plastic imitations. It can also…
Turquoise Treatments and Synthetics
According to some estimates, less than 5% of all turquoise mined worldwide is suitable for gem use without enhancement. Consequently, turquoise…
Turquoise Appraising
As a gemologist and appraiser living in the American Southwest, I’m often asked about turquoise. My customers usually have three main concerns…
Gray Diamond Value, Price, and Jewelry Information
Diamonds with a pure gray hue are a rare treasure indeed. More often, gray is mixed with blue or violet hues, but it can present as a modifying hue alongside…
Green Diamond Value, Price, and Jewelry Information
Green diamonds are the oddballs of the fancy colored diamond varieties. Their rare color is usually the result of damage from prolonged exposure…
Appraising Turquoise: Challenges for Gemologists
What do gemologists need to know when appraising turquoise? Learn what are the main value factors to consider and the challenges you’ll face.
Turquoise Treatments and Synthetics Guide
Almost all turquoises receive enhancements for jewelry use. Learn how to identify the most common turquoise treatments and synthetic options.…
Yellow Diamond Value, Price, and Jewelry Information
When someone mentions diamonds, the first image that most people think of is the colorless variety. It may surprise you to learn that only a tiny…
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