Spinel is singly refractive. However, a synthetic spinel may show anomalous double refraction (ADR). Testing gemstone refraction with a polariscope can identify ADR. Silver pendant with synthetic spinel. Photo by gosiko. Licensed under CC By-SA 3.0.
Lab-Created Blue Spinel Faceted in Pendant
Spinel is singly refractive. However, a synthetic spinel may show anomalous double refraction (ADR). Testing gemstone refraction with a polariscope can identify ADR. Silver pendant with synthetic spinel. Photo by gosiko. Licensed under CC By-SA 3.0.
Article: Polariscope Guide, Part 1: Testing Gemstone Refraction
Credit: gosiko
| Gemstone | Spinel |
| Natural or man made | Lab-made |
| Jewelry type | Pendant |
| Gem State | Faceted |
| Color | Blue |
| Transparency | Transparent |