Onyx is a chalcedony quartz that is mined in Brazil, India, California and Uruguay. Originally, almost all colors of chalcedony from white to dark brown and black were called onyx. Today when we think of onyx we often preface the word with black to distinguish it from other varieties of onyx that come in white, reddish brown, brown and banded. A variety of onyx that is reddish brown with white and lighter reddish bands is known as sardonyx, from the Greek sarx (flesh) because of these flesh tones in the gem.

The name also comes from the Greek word onyx which means nail of a finger or claw. Legend says that one day while Venus was sleeping Eros/Cupid cut her fingernails and left the clippings scattered on the ground. Because no part of a heavenly body can die, the gods turned them into stone which later became known as onyx.

Sardonyx is said to grant intelligence and courage, dispel nightmares and meloncholy, and break curses. Sardnyx is one of the stones in the ‘Breastplate of Judgement’ of Aaron, described in the Bible (Exodus 28:15-30). Sardonyx is also included in the listing of the gems of the King of Tyre (Ezekiel 28:13) and is one of the gems the New and Heavenly Jerusalem is said to be built of (the book of Revelation).

One of the earliest writers to associate the symbolism of the gems given in Revelation  with the apostles is Andrew, bishop of Caeserea. He gives says the sardonyx represents James, the (step) brother of Christ, a son of Joseph from his first marriage.

During the Renaissance in Europe it was believed that this stone gave speakers eloquence when talking. In Ancient Greece people used to carve them into the shape of scarab beetles, a mythological creature that was believed to eat people! The gem also has many links with royalty and it is said that Queen Elizabeth I gave the Earl of Essex a large Sardonyx gold ring as a present.