Epsomite
orthorhombic disphenoidic
this crystal shows 10 faces
pinacoid {010}
d = 1.000
2 faces
orthorhombic prism {110}
d = 0.600
4 faces
orthorhombic disphenoid {111}
d = 1.100
4 faces
unit cell : a = 11.96 b = 12.05 c = 6.88