The name comes from the Greek word, onux, which means fingernail. While most fingernails aren’t black, in Greek times, almost all colors of chalcedony, from fingernail white to black and everything in-between, were referred to as Onyx. Romans eventually applied the term to describe black and dark brown colors only.

Black Onyx is found worldwide but most commonly in Brazil, Madagascar and India. It has a hardness value of 7. Black Onyx is often heated to enhance the richness of color.

It is the alternate birthstone for February, the mystical birthstone for December and a lucky charm for the astrological sign of Leo. It is also the anniversary gemstone for the 10th wedding anniversary.

Some believe Black Onyx has the power to help change a person’s bad habits. It is also believed to be a valuable tool for helping concentration levels in absentminded people and to calm a chaotic life. In India it is believed to have the power to calm the ardors of love. It’s further thought to make the wearer eloquent and thus worn for public speaking engagements or to help lovers find the right words in weaving their spell of love on a new romantic interests. It is said to encourage the growth of fingernails, hair and skin.