Sardonyx is a variant in which the colored bands are sard (shades of red) rather than black. Black onyx is perhaps the most famous variety, but is not as common as onyx with colored bands. Artificial treatments have been used since ancient times to produce both the black color in "black onyx" and the reds and yellows in sardonyx. Most "black onyx" on the market is artificially colored.
Use of sardonyx appears in the art of Minoan Crete, notably from the archaeological recoveries at Knossos.
Onyx is mentioned in the Bible several times. Sardonyx is mentioned in the Bible as well.