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…
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…
Clarity Grading for Colored Gemstones
Don’t underestimate the importance of clarity, one of the Four Cs of gemstone grading. For faceted gems, basic clarity grading involves…
Distinguishing Diamonds: Educating Your Eyes
Step 4: Gem Grading Lesson 10 Back to syllabus Distinguishing diamonds from their lookalikes is a prerequisite to diamond grading. Assigning…
Gemology Cheat Sheets
Use these gemology cheat sheets to review color and clarity grading, as well as special information on diamond and opal. You can also review basic…
Buying Gems: Test Your Identification Skills
Step 3: Practical Gemology Lesson 30 Back to syllabus In this set of gemstone identification quizzes, I’m placing you in a familiar situation.…
Refractometer Guide, Part 1: Refractive Index Testing
Step 3: Practical Gemology Lesson 4 Back to syllabus Gemstone identification is like detective work. You gather clues and eliminate suspects…
Polariscope Guide, Part 1: Testing Gemstone Refraction
The polariscope is one of gemology’s simplest and most useful tools. With a little practice and our three-part polariscope guide, you’ll…
Polariscope Guide, Part 3: Testing For Gemstone Twinning, Dichroism, and Crystal Strain
A gemologist can conduct many different tests with a polariscope. Gemstone twinning, dichroism, and internal crystal strain are some of the properties …
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