Bentorite is a mineral with the chemical formula Ca₆(Cr,Al)₂(SO₄)₃(OH)₁₂·26(H₂O). It is colored violet to light violet. Its crystals are hexagonal to dihexagonal dipyramidal. It is transparent and has vitreous luster. It has perfect cleavage. It is not radioactive. Bentorite is rated 2 on the Mohs Scale.