akrochordite

akrochordite

[‚ak·rō′kȯr‚dit]
(mineralogy)
Mn4Mg(AsO4)2(OH)4·4H2O Mineral consisting of a hydrous basic manganese magnesium arsenate and occurring in reddish-brown rounded aggregates; hardness is 3 on Mohs scale, and specific gravity is 3.2.