Destructive Gemstone Tests: Acid Testing
In some cases, a hot point test won’t distinguish plastic simulants from natural gems. Some plastics release a protein smell when hot point…
Gemstone Magnetism: The Forgotten Property
Although gemstone magnetism isn’t a commonly tested gemstone property, it may be useful for making quick separations outside the lab. By Richard…
Destructive Gemstone Tests: Streak Testing
Gemstone streak testing is fun if you have rough material to spare. It’s not recommended for finished gems, as there’s a good chance…
Gemstone Physical Properties
Step 2: Advanced Gemology Lesson 2 Back to syllabus The optical properties of gems attract our eyes and can give a cut stone a unique character. However,…
Gemstone Radiation Treatment
Most gems on the market today receive various treatments to change their natural colors and create more desirable, salable products. Radiation…
Gem Formation: How are Gemstones Created?
Most gems form naturally as minerals within the Earth. Most form as crystals, solids whose atoms are arranged in highly ordered repeating patterns…
What are Crystal Systems and Mineral Habits?
In crystallography, mineral habits refer to the way crystals form within a specific mineral. In A Guide to Gem Classification, I mentioned that,…
Gemstone Toxicity Table
Gem faceters and jewelry enthusiasts alike should learn about gemstone toxicity. This table has toxicity ratings for 280+ gems, based on their…
What is Your Gemstone Personality?
Think of jewelry stones as reflections of you or the recipient. Learning about colored gems can help you find the gemstone personality you’re looking…
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