Diamond Rarity, Quality, and Cost
Word is out that diamonds aren’t that rare. So, why are they still so expensive? Learn about diamond rarity and quality and how they impact cost.…
White Sapphires vs Diamonds
Do white sapphires make good alternatives to diamonds? Compare their qualities and learn how to choose the right engagement ring stone for you.…
Advanced Gemology Equipment
We often recommend that novice gemologists send gems that are difficult to identify to a laboratory for testing. Gemological and mineralogical…
Destructive 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…
Destructive Hot Point Testing
Hot point testing can determine if some gem materials are plastic imitations. It can also reveal if a stone is treated with wax or plastic. By Donald…
Destructive Testing with a Streak Plate
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…
Destructive Testing with a Hardness Kit
Scratch testing can help determine the Mohs hardness value of a mineral sample. If done carefully, this procedure can help gemologists identify…
Gemstone Magnetism
Although gemstone magnetism isn’t a commonly tested gemstone property, it may be useful for making quick separations outside the lab. By Richard…
Tips for Measuring Specific Gravity
Step 3: Practical Gemology Lesson 10 Back to syllabus Getting accurate readings when testing gemstone specific gravity is critical. If you make…
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