( n. )
An earthy oxide of manganese, or mixture of different oxides and water, with some oxide of iron, and often silica, alumina, lime, or baryta; black ocher. There are several varieties.
( n. )
An earthy oxide of manganese, or mixture of different oxides and water, with some oxide of iron, and often silica, alumina, lime, or baryta; black ocher. There are several varieties.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012