- a common mineral consisting of a mixture of pyrolusite and other oxides of manganese, usually found in black, rounded masses: an ore of manganese.
Origin of psilomelane
1825–35; < Greek psīló(s) bare, smooth + mélan, neuter of mélas black
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Examples from the Web for psilomelane
Manganese occurs mainly as black oxide (MnO2) in the mineral pyrolusite; and, in a less pure form, in psilomelane and wad.A Textbook of Assaying: For the Use of Those Connected with Mines.
Cornelius Beringer and John Jacob Beringer
As an ore of manganese it is much less abundant than pyrolusite or psilomelane.
- a common black to grey secondary mineral consisting of hydrated basic oxide of manganese and barium: a source of manganese. Formula: BaMn 9 O 16 (OH) 4Also called: romanicite
C19: from Greek psilos bare + melas black
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012