Gemstone Identification Quizzes: Testing Procedures
By now, you know that gemstone identification is like detective work. As a gemologist, you gather clues and eliminate possibilities through a…
The Spectroscope in Gemology
Step 3: Practical Gemology Lesson 3 Back to syllabus Sometimes, refractive index (RI) and specific gravity (SG) readings aren’t enough…
Specific Gravity Testing Part 4: Refining Your Specific Gravity Testing Techniques
Step 3: Practical Gemology Lesson 10 Back to syllabus Getting accurate readings when testing gemstone specific gravity is critical. If you make…
Ultraviolet Testing and Gemstone Identification
Gemstone identification typically starts with measuring a specimen’s refractive index (RI) and specific gravity (SG). These two tests…
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…
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…
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,…
Impurity Ions and Gemstone Colors
I’ve faced many questions about the element chromium (Cr), the red coloration of minerals, and the gemstone red beryl. One of the many…
What are Gemstone Enhancements?
Gemstone enhancements are applied to gems to improve their appearance and wearability. Some of these procedures have been used for centuries,…
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