Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
Qualitative chemical analyses show (apart from Pb and Mo as major elements) non-negligible amounts of Fe and Cu.
Habit:
usually as combinations of {101} and {112}, sometimes with less developed {104} facets; sometimes more elongated crystals, composed of very steep quadroctahedra with curved faces
Thier des Carrières, Cahay, Vielsalm, Luxembourg, Wallonia, Belgium