AM_Klyuchevskite Formula: K3 Cu3 (Fe.82 Al.18) S4 O18 Name: Klyuchevskite Unit cell: 18.667 4.94 18.405 90.0 101.5 90.0 , V=1663.14 Space group: I121 (5)

Gorskaya M G , Filatov S K , Rozhdestvenskaya I V , Vergasova L P , Mineralogical Magazine , 56 (1992) p.411-416, The crystal structure of klyuchevskite, K3Cu3(Fe,Al)O2(SO4)4,, a new mineral from Kamchatka volcanic sublimates, Locality: Tolbachik Main Fracture Eruption, Kamchatka Peninsula, Russia