Gemstone information: Garnet is not a single mineral, but describes a group of several closely related minerals. Garnets come in a variety of colors and have many different varieties. However, the most widely-known color of Garnet gemstones is dark red. Red garnets have a long history, but modern gem buyers can pick from a rich palette of garnet colors: greens, oranges, pinkish oranges, deeply saturated purplish reds, and even some blues. Red garnet is one of the most common and widespread of gems. But not all garnets are as abundant as the red ones. A green garnet, tsavorite, is rarer and needs rarer rock chemistries and conditions to form.