The Optical Properties of Gemstones
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…
The Physical Properties of Gemstones
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,…
A Brief History of Diamonds
Diamonds have a rich history. The earliest diamond deposits date back 900 million years. To put that into perspective, the Earth is approximately…
A Brief History of Famous Diamonds
No other precious gem is as familiar — and coveted — as diamond. Learn the legends and histories behind some of the most famous diamonds in the…
Identifying Synthetic Gems
Distinguishing natural from synthetic gems is a critical skill for gemologists. It could mean the difference between valuing a gemstone at thousands…
Identifying Synthetic Diamonds
Step 5: Advanced Gem Information Lesson 2 Back to syllabus Synthetic diamonds aren’t new. General Electric (GE) has been making them since…
An Introduction to Gemstone Grading
Although gemologists look at color, clarity, cut, and carat to evaluate both diamonds and colored gems, they must judge these qualities in the…
Evaluating Gemstone Cutting: The Five Ps
Step 4: Gem Grading Lesson 3 Back to syllabus In recent decades, something remarkable invaded the thinking process of the colored stone industry.…
Recutting Diamonds and Colored Gemstones
As a professional gemologist, you’ll grade and value gems. Occasionally, you’ll come across a stone that may need recutting. However,…
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