Properties of Diamond Simulants
Diamond simulants often appear in jewelry, as side stones and accents as well as centerpieces. Identifying these lookalike materials, whether…
Using Your Refractometer
Step 3: Practical Gemology Lesson 4 Back to syllabus Gemstone identification is like detective work. You gather clues and eliminate suspects…
Recommended Diamond Grading Tools for Novices
You need the right equipment to identify and grade natural diamonds. Just as with colored gemstones, your ultimate objective will guide your choice…
Gem Formation: How are Gemstones Created?
Most gems form naturally as minerals within the Earth. Most form as crystals, solids whose atoms are arranged in highly ordered repeating patterns…
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…
What Does the L/W Ratio Mean in Gem Cutting?
Gem cutters use the “length-to-width” or L/W ratio to determine how to cut rough gems. Learn how to choose gem designs based on a stone’s L/W…
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…
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