gem, ornamental mineral or organic substance: Other Gemstones

The cutter of gemstones other than diamonds is known as a lapidary. Precious and semiprecious stones other than diamonds are cleaved or slit by a revolving diamond-dusted wheel, faceted by being pressed against a lap (a smoothing and polishing tool) charged with diamond dust or a carborundum wheel, and polished with a softer abrasive. Most (and in the case of some gems all) of the work of faceting is done with only the eye of the lapidary as guide.

Sections in this article:

• Introduction
• Counterfeit Gemstones
• Precious and Semiprecious Gemstones
• Other Gemstones
• Diamond Cutting
• Gem Cutting
• Properties of Gems
• Bibliography

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2024, Columbia University Press. All rights reserved.

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