Jasper is a form of chalcedony, and is an opaque variety of silica. Jasper is an opaque rock of virtually any color stemming from the mineral content of the original sediments or ash. Patterns arise during the consolidation process forming flow and depositional patterns in the original silica rich sediment or volcanic ash.
The name means “spotted or speckled stone”, and is derived via Old French jaspre. Jasper was a favorite gem in the ancient world including Arabic, Persian, Hebrew, Assyrian, Greek and Roman cultures. On Minoan Crete, jasper was carved to produce seals circa 1800 BC, found at the palace of Knossos.