Ammineite is the first recognized mineral containing ammine groups. Its formula is [CuCl2(NH3)2]. The mineral is chemically pure. It was found in a guano deposit in Chile. At the same site other ammine-containing minerals were later found:Mindat, Pabellón de Pica, http://www.mindat.org/loc-192704.htmlMindat, Chanabayaite, http://www.mindat.org/min-43945.htmlMindat, Joanneumite, http://www.mindat.org/min-42755.htmlMindat, Shilovite, http://www.mindat.org/min-46139.html
Chanabayaite, CuCl(N3C2H2)(NH3)·0.25H2O (an alternative formula), a triazolate mineral Joanneumite, Cu(C3N3O3H2)2(NH3)2, an isocyanurate mineral Shilovite, Cu(NH3)4(NO3)2
Crystal structure The characteristic features of the structure of ammineite are: layers of trans form of the copper complex, parallel to (001), connected by Cu-Cl bonds presence of CuN2Cl4 distorted octahedron ([4+2] coordination) edge-sharing of the octahedra produce zigzag chains along the direction hydrogen bonds between NH3 and Cl atoms
Associated minerals Ammineite coexists with atacamite, darapskite, halite and salammoniac.
Origin Ammineite is supposed to be a result of an interaction of an earlier copper mineral, likely from a plutonic rock, with ammonia in guano. Ammonia may be produced in decomposition of compounds like urea or uric acid.
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