Gemstone Doublets, Triplets, and Other Assembled StonesGemstone Doublets, Triplets, and Other Assembled Stones

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Gemstone Doublets, Triplets, and Other Assembled Stones

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Are Assembled Gemstones Natural or Synthetic?

While the component parts of gemstone doublets and other creations may occur naturally, the assembled stones themselves aren’t natural. For example, a gem cutter may cement a thin layer of natural opal onto a layer of natural onyx. These components are natural, of course, but the combined piece isn’t. Sometimes, assembled stones also include synthetic components like glass and plastic.

Read this article on gem classification for more information about natural, synthetic, and imitation gems.

Why Do People Create Assembled Gemstones?

Some common reasons are:

  • Making use of otherwise unsuitable or fragile gem material.
  • Creating an entirely new category of gem product.
  • Providing an inexpensive simulant for an expensive natural gem.
  • (Unfortunately) deceiving a buyer into thinking a piece is something more valuable.

Gemstone Doublets and Triplets

Most gem enthusiasts will recognize doublets and triplets, especially the opal varieties. Opals frequently occur as thin seams of material within a host or matrix rock. Although beautifully colored, some deposits are too thin and fragile to be used for jewelry. However, cementing one of these thin layers onto a strong backing, such as black onyx, black opal, or something similar, creates a doublet or triplet….

Barbara Smigel, PhD. GG

Barbara Smigel is a GIA certified gemologist, facetor, jewelry designer, gem dealer, gemology instructor and creator of the well-regarded educational websites and

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