Pyrolusite

This specimen, from the Caland Mine in Ontario, showcases sharp, short prismatic crystals of pyrolusite with a striking silvery luster, forming a fine miniature example. Pyrolusite, a manganese oxide mineral, is known for its variable hardness—typically soft enough to smudge fingers but, in well-crystallized forms like this, harder than glass. The mineral forms as a weathering product of other manganese minerals, exhibiting a metallic sheen and dark coloration.

The Caland Mine, famous for its iron production, played a significant role in Canadian and U.S. WWII efforts, supplying vast amounts of iron ore. Located near Atikokan, Ontario, this historic mine was a key resource during the mid-20th century, and specimens like this are valuable both mineralogically and historically.