ONYX

Onyx is a chalcedony that occurs in bands of different colours. Onyx refers to a black and white banded variety of Agate and brown varieties are named Sardonyx. It is composed of relatively straight, parallel layers of different colours. This structure lends itself to cameo making. 
It is usually cut into cabochon, or into beads, and is also used for intaglios and cameos. Some onyx is natural but much is produced by the staining of agate. It is available in the regions of USA, Germany, Brazil, Mexico, India, and Africa.

Colour : Black.
Hardness : 7

Onyx focuses and directs your energy toward your goals, helping you stay the course. It can help you rebuild your vitality after a prolonged illness or period of depletion, and is useful for work that requires disciplined focus and perseverance.