doublet

gem

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Last updated

June 25, 2026

Quick Summary

A doublet is a type of assembled gem, meaning it's a cut gemstone made from two or three pieces cemented together to appear as a larger, more valuable stone.1

A doublet specifically consists of two pieces joined at the girdle. If both pieces are the same material, it's a true doublet. If the top part (crown) is genuine and the bottom part (pavilion) is an inferior material or glass, it's a false doublet. These can be identified by immersion in liquids that reveal the cement line or differing appearances of the two halves.1

Doublets are often made using materials like glass, zircon, topaz, quartz, or garnet to imitate more precious stones such as diamonds or rubies.1

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assembled gem
A doublet is composed of two pieces of material, usually cemented together at the girdle (the stone’s widest part): if the two pieces are of the same material, the gem is called a true doublet; if they are different, with the crown (above the girdle) being…
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A doublet is composed of two pieces of material, usually cemented together at the girdle (the stone’s widest part): if the two pieces are of the same material, the gem is called a true doublet; if they are different, with the crown (above the girdle) being…
Read More