Red garnets, like this almandine, may also resemble rubies. However, unlike rubies, garnets have no birefringence. Gemologist can used a dichroscope to test for birefringence. But, some almandines may show anomalous birefringence or anomalous double refraction (ADR). A polariscope test can help spot ADR. Photo by Didier Descouens. Licensed under CC By-SA 3.0.
Red Almandine Garnet Faceted
Red garnets, like this almandine, may also resemble rubies. However, unlike rubies, garnets have no birefringence. Gemologist can used a dichroscope to test for birefringence. But, some almandines may show anomalous birefringence or anomalous double refraction (ADR). A polariscope examination can help spot ADR. Photo by Didier Descouens. Licensed under CC By-SA 3.0.
Article: An Introduction to Gem Identification
Credit: Didier Descouens
| Gemstone | Garnet, Almandine Garnet |
| Natural or man made | Natural |
| Gem State | Faceted |
| Color | Red |
| Transparency | Transparent |