This great old material came from a mine for Manganese in Montana near the Canadian border. It is soft and easily carved with files or a hacksaw, and takes a smooth luster. It contains beautiful black "flowers", which is really one of the ways Manganese crystallizes. The stone is whitish gray. This one is 7.5" x 4.5" x 4, and weighs 9.60 lbs.  UNUSUALLY LARGE PIECE!