A variety of gemstones have been found in Nevada, and the state is well-known for its opal. After Australia, some of the finest black opals in the world come from Virgin Valley, Nevada. The specimen shown here is a 9-millimeter faceted yellow fire opal of about 1.79 carats, cut from rough produced in Nevada. The state is also well-known for its turquoise, petrified wood, agate, jasper, and obsidian.