Psilomelane

Name:
Psilomelane
Detailed information:

M Formula:	BaMn9O16(OH)4
Properties:
Black color, brownish-black streak, submetallic luster. Hardness 5–6, d 3.7–4.7.
Occurrence:
The former U.S.S.R., India, South Africa, Cuba, U.S. (Arkansas, Virginia, Georgia).
Use:
Important ore of manganese.