Chanabayaite
Chanabayaite is the first recognized triazolate mineral, having the formula.
Minor iron admixture is also present. It is also one of a few currently known minerals containing ammine groups, including also ammineite, joanneumite and shilovite. All the minerals are rare and were found in a single guano deposit in Chile, called Pabellón de Pica. A similar natural phase, formula, likely a precursor of chanabayaite, is described by Zubkova et al. 2016.
The main features of the crystal structure of chanabayaite are:
Association
Chanabayaite coexists with halite, joanneumite, nitratine, salammoniac and paragenetically-unrelated chalcopyrite. Chalcopyrite is present in an amphibole- and plagioclase-bearing gabbro, that contacts the guano deposit.
Formation
Three suggested processes account for the formation of chanabayaite:
- leaching of sodium from the precursor phase
- leaching of chlorine from the precursor phase
- partial dehydratation of the precursor phase