Many people purchase gems by type - for example, they want to buy a sapphire, a tourmaline or an amethyst. Finding gems by color can often be hard, since sellers organize their inventory around gem varieties rather than colors. Here is a list of gem types organized by color.
Red
Red gemstones are actually quite rare, and mainly occur in ruby, spinel and garnet. There is some very fine red tourmaline (sometimes called rubellite), but it is not often found.Ruby
The most popular pink gemstones are tourmaline and spinel. Pink sapphire is beautiful but rare.Sapphire
Blue
The classic blue gemstone is sapphire. Deeply saturated blue is also found in spinel.Sapphire
Green
The traditional green gem is emerald, but tsavorite garnet, chrome tourmaline and chrome diopside are good alternatives. Peridot, which is olive green, is now a popular gemstone.Emerald
Yellow/Gold
Citrine is the most common yellow to gold gem.Citrine
Violet/Purple
Amethyst is the classic example, though fluorite can also be found in an amethyst-like purple.Amethyst
Orange
Spessartite garnet is the most famous orange gem but there are a number of others.Spessartite Garnet