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 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,…
Gemstone Color Change Phenomena
People frequently ask me to explain how gemstone color change works. Some stones can change color under different types of light sources. Although…
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,…
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…
HPHT Diamond Update
Step 2: Advanced Gemology Lesson 8 Back to syllabus In 1999, General Electric (GE) introduced a new diamond treatment into the jewelry trade. The…
Identifying Inclusions Found in Synthetic Gems
One of the simplest ways to distinguish natural from synthetic gems is finding inclusions that can only be the result of laboratory growth. You…
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