Onyx is the Mystical birthstone for the month of December. It is also the birth stone for the Zodiac sign of Leo. It is also given on the 7th and 10th wedding anniversary.
The name 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. Onyx is mined in Brazil, India, California and Uruguay. It has a fine texture and black color; however some onyx also displays white bands or ribbons against a black or brown background and this variety is known as sardonyx. Most Black Onyx that is commercially available today is color enhanced (heated and dyed) to increase it's depth of color.
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. Onyx is a very good stone for use in carving.
Composition: Chalcedony quartz
Mohs-Scale Hardness: 6.5