AM_Pentahydrite Formula: (Mg.45 Cu.55) S O9 H10 Name: Pentahydrite Unit cell: 6.249 10.5846 6.0384 82.461 109.433 104.805 , V=363.67 Space group: P-1 (2)

Peterson R C , Hammarstrom J M , Seal R R , American Mineralogist , 91 (2006) p.261-269, Alpersite (Mg,Cu)SO4*7H2O, a new mineral of the melanterite group, and cuprian, pentahydrite: Their occurrence within mine waste, Locality: Big Mike mine, Nevada, USA