Vintage Engagement Rings: Guide to Four Eras
Vintage engagement rings come in many different styles, but designs from four eras are very popular today. Learn more and find that perfect vintage…
Table of Refractive Indices and Double Refraction of Selected Gems
Refractive indices and double refraction (birefringence) help gemologists identify gems. The following table lists these values for selected…
Utopia: Online Faceting Designs and Diagrams
Jeff Graham’s Utopia gem design is a large Barion pear cut for light to medium-colored stones. Learn about this advanced design for experienced…
Introduction to Gem Cutting Styles
While some cut names may describe the face-up shape of the finished gem, others refer to the shape and arrangement of the gem’s facets. These cuts…
Understanding Yellow Diamonds
3.75-ct emerald-cut fancy yellow diamond with Burmese rubies. © Jogani Beverly Hills. Used with permission. Perhaps the most fantastic…
Carats and Gemstone Grading
Step 4: Gem Grading Lesson 2 Back to syllabus A carat is the standard unit of measurement for weighing gems, and it’s one of the Four Cs of gemstone…
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…
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…
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…
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