The term "sardonyx" originates from the ancient Greek word "sardonux" (σαρδόνυξ), which is a combination of "sard" (σάρδιος), a reddish-brown chalcedony, and "onyx" (ὄνυξ), which means "fingernail" or "claw". They thought this layered stone resembled a fingernail and fingertip. Usually it was employed in cameos, and this is a totally novel use for it.