Gemology Cheat Sheets
Use these gemology cheat sheets to review color and clarity grading, as well as special information on diamond and opal. You can also review basic…
Difficult Gemstone Separations
Step 3: Practical Gemology Lesson 27 Back to syllabus While some gems are fairly easy to distinguish, others present greater challenges to gemologists.…
Gemstone Examination Lesson
Step 3: Practical Gemology Lesson 28 Back to syllabus While preparing this lesson in gemstone examination, I was in the process of professionally…
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: Scratch Testing
Scratch testing can help determine the Mohs hardness value of a mineral sample. If done carefully, this procedure can help gemologists identify…
Gemstone Optical Properties
We tend to take light for granted. It’s such a common thing we experience every day. Rarely do we think of the scientific definition of light…
A Beginner’s Guide To Common Gemstone Heat Treatments
Gemstone heat treatments can turn mediocre pieces into items of great beauty. Heating a gem to a specific temperature and then cooling it is a common…
Gemstone Radiation Treatment
Most gems on the market today receive various treatments to change their natural colors and create more desirable, salable products. Radiation…
A Guide to Gem Cutting Styles
While some cut names may describe the face-up shape of the finished gem, others refer to the shape and arrangement of the gem’s facets. These cuts…
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