Properties of Diamond Simulants
Diamond simulants often appear in jewelry, as side stones and accents as well as centerpieces. Identifying these lookalike materials, whether…
Introduction to Diamond Treatments
Even as new diamond treatments enter the market, old techniques are revised and improved. Learn how to identify the most common current treatments.…
Lab-Created Diamonds: the Ultimate Guide
Lab-created diamonds have an undeserved stigma. However, they make excellent, lower cost alternatives to natural, mined diamonds. In this article,…
How to Measure an “Over The Limit” Refractive Index
A gemstone with a refractive index (RI) reading that exceeds 1.81 is said to be “over the limit” (OTL). Low-cost refractometers can’t…
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…
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…
Phenomenal Gems – Unique Phenomena in Gemstones
Some optical effects in gemstones, such as color, brilliance, and dispersion, can be quite impressive. However, not all optical effects are considered…
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