The Mineral Jasper

Jasper is an opaque form of Chaledony, which is a micocrystalline variety of the mineral Quartz. It often contains an abundance of impurities, and therefore some regard it as a rock instead of a mineral. Jasper is usually associated with brown, yellow, or reddish colors, but may be used to describe other opaque colors of Chalcedony such as dark or mottled green and orange. Some forms of Jasper are ganded, and these banded Jaspers may appear similar to Agate, but unlike Agate they are opaque.