Garnets are the birthstone for January. Perhaps most people think “red” when they hear the word garnet, but there are a lot of garnet varieties – all with different colors ranging from yellows and greens to shades of red, orange red, and reds with a hint of blue or violet.
These color variations are the result of slight differences in chemical make-up among the varieties: Pyrope garnets are red with a brownish tint; Rhodolite garnets are a rose or purplish red; Almandite garnets are red with a violet tint; Spessartite garnets are orange to red-brown; Grossularite garnets include both Hessonite garnets which are cinnamon red-brown and also Tsavorite garnets which come a range of green shades. Yet another variety is Andradite garnets which include green Demantoid garnets – perhaps the most valuable garnet variety.
Garnets have a Mohs hardness index of 6.5 to 7.5 – ideal to use for most jewelry items.
For more information about garnets and some photos of other varieties, check out these links: