AM_Trigonite Formula: Pb3 Mn As3 O9 H Name: Trigonite Unit cell: 7.26 6.78 11.09 90.0 91.5 90.0 , V=545.69 Space group: P1N1 (7)

Pertlik F , Tschermaks Mineralogische und Petrographische Mitteilungen , 25 (1978) p.95-105, The crystal structure of trigonite, Pb3Mn(AsO3)2(AsO2(OH)), Locality: Langban, Varmland, Sweden