These hausmanite crystals are from the Wessels mine at Hotazel, Kalahari Manganese Fields, Northern Cape Province, South Africa. The Wessels Mine is a manganese mine started in 1973. It contains 125 different minerals including the oxide hausmanite. It contains the elements Mn and O. This specimen is a plate-like formation of elongated leaf-like crystals. They have a silver black color and a sub metallic luster with a shimmering quality. This piece measures approximately 3 1/4 x 2 5/16 x 7/8 inches or 83 x 59 x 22 mm.