Although used in the Mediterranean area since ancient times, Tourmaline was recognized as a separate gemstone only in the early 19th century. Prior to that time, it was generally confused with other gemstones. The name is believed to derive from the Sinhalese turamali, meaning "multi-colored stone". Most people think only of the "watermelon" variety of the gem. But in fact tourmalene can occur in nearly every color of the rainbow, and each variety is named for its predominate color. Rubellite (pink tourmaline) can rival the ruby in color. The best grades are rarer than ruby or spinel and can be nearly as expensive. Other popular varieties include verdelite (green tourmaline) and indigolite (blue or blue-green tourmaline). In the jewelers' trade all green tourmaline, regardless of type, is known as chrome tourmalene. The color ranges from bright kelly green to dark teal green. The price is usually low enough to make it an economical subsitute for emerald.