Sugilite Value, Price, and Jewelry Information
What is the color of sugilite? Grape jelly purple is a good description. More popular among consumers in Asia than North America, this is a very rare…
Before and After: Pictures of Repaired and Recut Gems
Take a look at these before-and-after pics of repaired and recut gems and learn how a great lapidary can improve the value of many types of gems.
Signature #4: Online Faceting Designs and Diagrams
The Signature #4 is Jeff Graham’s favorite trillion cut for light-colored gemstones. This popular design is also fast and easy to cut.
Lapidary Technology Through the Ages: Laps and Polish
Early lapidary technology doesn’t differ from our modern tools as much as you might think. Learn more about the history of laps, polish, and gem…
Grading Set Stones
Step 4: Gem Grading Lesson 4 Back to syllabus Few gemologists deal strictly with loose stones. Occasionally, most may have to grade set gemstones.…
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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