African onyx – Raw

African onyx is a natural gemstone found in Africa. Its raw form has a unique parti-colored pattern that makes it perfect for use in jewelry and sculpture. Additional features include durability, luster, and a subtle sheen - making it a great choice for both professionals and hobbyists.

Crystal: Onyx. 
Country of origin: India. 
Chemical composition: SiO2. 
Hardness based on Mohs scale: 7. 

Onyx wikipedia