Black Onyx

Onyx is a chalcedony quartz that 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. 

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. 

Most Black Onyx that is commercially available today is color enhanced (heated and dyed) to increase it's depth of color.