hybrid gemstones - glass ruby
hybrid gemstones - glass ruby

Hybrid Gemstones: Glass Rubies and More


Some gems contain both natural and lab-made components. Learn about these hybrid gemstones and how to distinguish them from mined gems.

3 Minute Read

What are Hybrid Gemstones?

The term “hybrid” hasn't been clearly defined in the industry. Some use the term to refer to any combination of mined and synthetic material. This includes assembled gems such as doublets, triplets, and mosaics.

Others will only apply the term to stones where differentiating the natural material from the treatment is difficult, if not impossible. These stones may be the results of reconstitution, polymer impregnation, or leaded-glass treatments.

Growing lab-created material over a mined gem can also create hybrid gemstones. Although such synthetic overgrowth is uncommon in today’s colored gemstone market, older stones occasionally resurface. Diamond hybrids are somewhat more common. These can contain a chemical vapor deposition (CVD) layer over natural diamond to increase weight or improve color. Other diamond hybrids have a layer of diamond-like carbon (DLC) over a non-diamond, colorless gemstone.

Leaded-Glass Rubies

Most who use the term “hybrid” first applied it to ruby-glass mixtures. This includes both fracture-filled stones and composites made of several small pieces of ruby in a glass matrix. In some cases, the glass component constitutes a significant portion of the stone’s size and weight. In extreme cases, the gemstone would hardly exist without the glass component. Some...


Addison Rice

A geologist, environmental engineer and Caltech graduate, Addison’s interest in the mesmerizing and beautiful results of earth’s geological processes began in her elementary school’s environmental club. When she isn’t writing about gems and minerals, Addison spends winters studying ancient climates in Iceland and summers hiking the Colorado Rockies.

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