What is a mineral, usually of a pale brown or of a gray or grayish green color, consisting chiefly of the hydrous silicate of iron and manganese; -- so called from the odor given off before the blowpipe called?

pyrosmalite — A mineral, usually of a pale brown or of a gray or grayish green color, consisting chiefly of the hydrous silicate of iron and manganese; -- so called from the odor given off before the blowpipe. (Webster's 1913.)