Teruggite is a mineral with the chemical formula Ca4MgAs2B12O22(OH)12·12H2O. It is colorless. Its crystals are monoclinic prismatic. It is transparent. It is not radioactive. It has vitreous luster. Teruggite is rated 2.5 on the Mohs Scale of hardness. References Webmineral data Mindat.org Handbook of Mineralogy Calcium minerals Magnesium minerals Arsenic minerals Nesoborates Monoclinic minerals Minerals in space group 14