Cartier keychain with blue synthetic spinel cabCartier keychain with blue synthetic spinel cab

Identifying Synthetic Spinel

Synthetic spinel is a widely used jewelry stone. Learn how gemologists can identify lab-made flame-fusion, flux, and Czochralski spinels.

11 Minute Read

How is Synthetic Spinel Made?

Currently, manufacturers mainly use two methods to grow synthetic spinel: flame fusion and flux. Although flux-grown spinels were accidentally created as early as the mid-19th century, according to Muhlmeister et al., they were not commercially significant as gemstones until the early 1990s. In contrast, flame-fusion spinels have been marketed as faceted gems since the 1920s. (81)

Flame-Fusion Spinel

The flame-fusion procedure, also known as the Verneuil method, involves dropping the powdered form of the constituent elements through a flame, which causes them to melt. This now fluid mixture falls on a pedestal. As this pedestal rotates, the gem solidifies in layers.

Flux Spinel

In the flux procedure, a hot flux material dissolves the elements needed for spinel into a solution. As this solution cools, it crystallizes. First identified on the gem market in the 1990s, flux-grown spinels require significantly longer growth times — and cost more — than their flame-fusion counterparts.

Czochralski Spinel

Spinels grown via the Czochralski or pulled process (a procedure similar to flame fusion) have also been documented. (See Saeseaw, Wang, and Scarratt and Segura and Lulzac).

Are Flame-Fusion Spinels True Synthetics?

There has been some discussion in

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