Pyrolusite
PhotosRoger Weller, geology instructor
wellerr@cochise.edu copyright 2008-R.Weller
pyrolusite crystals-1
Pyrolusite is manganese oxide. It
is a black, rather hard mineral (6 to 6.5) and is a
major ore of manganese.

pyrolusite
Photo is copyright free for
non-commercial educational uses.
Just credit photo to R.Weller/Cochise College.