Pyritohedron The "pyritohedron" crystal form is very common in pyrite. The actual name of this crystal form is pentagonal dodecahedron. This literally means it is a crystal with 12 face (dodeca means 12 and hedron means faces), and each face has 5 sides (pentagonal). Excellent pyrite crystals have been recovered at the Magma Mine, Superior, Pinal County.