The mineral hemimorphite (also called calamien) is a hydrated zinc-silicate having the chemical formula Zn4Si2O7 (OH) 2 · H2O. It belongs to the sorosilicaten. The mineral is used in particular as the oxidizing product in the upper layer of zincblende deposits. Known sites are the Belgian-German border, Silesia in Poland, and the states of Pennsylvania and Missouri in the United States. Hemimorphite is one of the most common sorosilicates. Its most outstanding feature is the polar or hemimorphic crystal from where it gets its name. The crystal structure has a different end to each end of the crystal. A notice of termination, the "bottom" is rather blunt is dominated by a Pedion face, while the other side, the "top" is terminated by the tip of a pyramid. The crystal structure contains tetrahedrons of ZnO 3 OH, locked with Si 2 O 7 groups and water molecules. The zinc is in the center of the tetrahedron while the three oxygen atoms, together with an OH-group, at the four points of the tetrahedron. The tetrahedra are all aligned in the same direction with a plane parallel to the Pedion termination and of the "top" of the tetrahedra direction of the pyramidal termination.
Gemstone therapy Hemimorphite (Dutch)