Onyx
on·yx | ˈä-niks
noun
A semi-precious stone that is black or white in color
Onyx is a member of the chalcedony family of minerals, generally considered porous stones. It is considered a semi-precious stone that is either white or black in color. The term Onyx has also been used to describe parallel banded versions of other minerals, including obsidian, opal, marble, and alabaster. The term is derived from the Latin and Greek terms for claw or fingernail because of the lighter colored bands within the stone that resembled fingernails at the time. Onyx is commonly used in flat jewelry designs such as cameos because of its layered structure.