topaz is a silicate mineral of aluminum and fluorine. topaz crystallizes in the orthorhombic system, and the crystals are often prismatic terminated by pyramidal and other faces.

Aquamarine, named for the Latin phrase "water of the sea", is the blue to blue-green variety Beryl. Beryl also contains other gem varieties, including Emerald, and some lesser known varieties such as Morganite and Heliodor.