In its black variety this is our favourite deep, dark, absorber of light. A black stone in its truest form, totally opaque. When we cannot source onyx we sometimes use black spinel instead, they look identical to the eye but spinel is harder to cut. 

Colours: various although we only use the black shade. 

Mohs scale: 6.5 - 7

Crystal Formation: Triagonal

Country of origin: Yemen, Uruguay, Argentina, Australia, Brazil, Canada, China, Czech Republic, Germany, India, Indonesia, Madagascar, Latin America, the UK, and various states in the USA.