Reference Charts & Materials
Commonly used charts and table for jewelers, lapidaries and gemologists.
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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Diamond Look-alike Comparison Chart
Distinguishing a diamond look-alike from the real thing can challenge new gemologists. However, specific gravity and birefringence hold the key...
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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
Our birthstone chart features both modern and traditional options. See galleries of birthstone jewelry by month and learn more about...
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