This sturmanite is from the Wessels Mine, Hotazel in the Kalahari manganese fields of the Northern Cape province of South Africa. The manganese fields contain the largest deposits of manganese on earth. They also contains over one 100 different associated mineral species including sturmanite. It is a sulfate that contains the elements Ca, Fe, S, O B and H.This is a double sided plate of druse sturmanite crystals that contains larger euhedral crystals on the display side. They are translucent and have a vitreous luster. This piece measures 1 1/8 x 1 x 9/16 inches or 28 x 25 x 14 mm.