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!
Meikle (1989): "Barite is present in a single occurrence closely associated with native copper, cuprite, and malachite, and also in prehnite-lined cavities in the tuffaceous horizon, as layered and interlocking groups of large, <2 mm thick, clear to white crystal tablets. In incompletely filled cavities barite is discoloured grey by admixed volcanic ash, but where cavities are completely filled it is only in the centre of the cavity that the crystals are discoloured. In one case the crystals taper uniformly in the same direction thus creating an appearance on cleaved faces of a radial structure."
