Tags: Chemical Substance, Mineral.
Pigeonite is a mineral in the clinopyroxene group. It has a general formula of (CaMgFe)(MgFe)Si2O6. The calcium cation fraction can vary from 5% to 25% with iron and magnesium making up the rest of the cations.Pigeonite crystallizes in the monoclinic system as does augite and a miscibility gap exists between the two minerals. At lower temperatures pigeonite is unstable relative to augite plus orthopyroxene.
