Description: Pyrite Rio Marina - Elba Island - Italy 2 cm The cubic form is absent in this crystal. The dominant form is pyritohedron (or pentagonal dodecahedron). But some apexes are truncated by secondary forms, such as the octahedron itself slightly truncated by a diploid (or didodecahedron). A diploid has 24 faces that are formed from the splitting of the pentagonal faces on the 12 sided pyritohedron.

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