(TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
Rammelsberg, C.F. (1841): Handwörterbuch des chemischen Theils der Mineralogie. Vol. 1, C.G. Lüderitz (Berlin), 3-5.; Forchhammer, [J.G.] (1864): Om Ædelforssit og nogle andre dertil hørende Mineralier. Oversigt over Det Kongelige Danske Videnskabernes Selskabs Forhandlinger. 64-76