Spessarite Garnet
Structure : CubicHardness : 7
Specific Gravity : 4.16
Refractive index : 1.79 - 1.8
Doubly Refracting (bi-refraction) : none
Color. Spessartite garnet is ideochromatic, meaning that it is colored by a fundamental element in its composition. That element is manganese, which produces an orange color. Take away the manganese, and it would no longer be spessartite. Thus spessartite has only one basic color – orange. That said, the color may be modified slightly by mixing with iron, in the form of almandine. This produces a deeper, more reddish coloration. Spessartites occur in three basic flavors. There are the light and bright stones, which come from Nigeria, Ramona (CA) and the deeper reddish orange stones that also come from Nigeria. Then there are the fabulous tangerine orange “mandarin” garnets from Namibia, which are in a class all by themselves.