turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminum. turquoise has a lower-than-ideal hardness and durability for use in certain types of jewelry.

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.