How Does Quartz Form?
Quartz is one of the most abundant minerals on earth. Learn how quartz forms and how its most popular varieties get their colors.
Common Gemstone Treatments Cheat Sheet
There are so many common gemstone treatments available today that keeping track of them can be difficult. This list and handy cheat sheet can help.…
Carving Techniques for Handling Inclusions in Transparent Gems
Inclusions don’t have to result in a loss of mass or value when cutting transparent gems. Learn how to manage inclusions with basic gem carving techniques.…
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…
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…
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…
Grading Gem Carvings
Gem carvings vary widely in size, shape, and quality. You can find small, simple carvings with a glued-on bail for just a couple of dollars. Fine…
Difficult Gemstone Separations
Step 3: Practical Gemology Lesson 27 Back to syllabus While some gems are fairly easy to distinguish, others present greater challenges to gemologists.…
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