Reference Charts & Materials
Commonly used charts and table for jewelers, lapidaries and gemologists.
Diamond Lookalikes Listed by Specific Gravity
Distinguishing diamond lookalikes from the real thing can be challenging. Learn how to use specific gravity and birefringence to make...
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Standard Gem Sizes Chart
Will your gem fit in a standard setting? Use this chart of standard gem sizes for popular cuts and also...
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Gemology Cheat Sheets
These gemology cheat sheets review gem color and clarity grading, specific information on evaluating diamonds and opals, and basic gem...
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How to Estimate Gem Weight in a Jewelry Setting
Although you can't weigh a gemstone in a jewelry setting, you can get a close approximation of the gem weight...
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Table of Gems Ordered by Crystal System
This table contains a selection of minerals gemologists may encounter as jewelry stones or gem specimens. The gems are sorted...
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Specific Gravity Values of Selected Gems
Measuring specific gravity helps gemologists identify gemstones. The following table lists the specific gravity values for a variety of gem...
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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 gemstones.
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Properties of Diamond Simulants
Diamond simulants, like cubic zirconia and moissanite, often appear in jewelry. See how the properties of real diamonds compare with...
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Bead and Necklace Size Charts
Whether you’re a novice bead jewelry maker or just shopping for necklaces, these bead and necklace size charts and links...
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The Mohs Hardness Scale and Chart for Select Gems
The Mohs hardness scale measures a mineral's resistance to scratching. Find the traditional scale here and a chart of select...
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List of False or Misleading Gemstone Names
A list of False or Misleading Gemstone Names and its Actual Gemological Name. Gathered by the source "Gemstones of the...
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Gem Structure Chart
A gem structure chart that shows various information on a specific structure and gems of example. Details include Refractive Indexes,...
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Ring Size Comparison Chart
Ring Size Comparison Chart compliments of the International Gem Society. A conversion table of Ring sizes. 7 different ring size...
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Weights and Measures Conversion Chart
Printable chart to convert weights and measures including Carats, Grams, Kilograms, Ounces, Pounds and Troy Ounces Pounds and Pennyweights.
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METAL/WAX FORMULAS
Jewelers need to know how to determine how much gold is needed for a wax mold. Here are three methods...
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Birthstone Chart
What are the birthstones by month? January is garnet, February is amethyst, March is aquamarine, April is diamond, May is...
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