wigmund: From Mindat.Org Photo Of The Day; October 29,…

wigmund:

From Mindat.Org Photo Of The Day; October 29, 2016:

Richardsollyite: TlPbAsS₃; Hutchinsonite: TlPbAs₅S₉

Locality: Lengenbach Quarry, Fäld (Imfeld; Im Feld; Feld), Binn Valley, Wallis (Valais), Switzerland

Richardsollyite, metallic grey-black crystals with striated and curved faces, grown on cherry-red hutchinsonite. Associated minerals are Tl-bearing dufrénoysite in tiny fibrous red-brown needles, orange-red realgar, fine-grained colourless dolomite and gemmy colourless barite. Photo Stefan Ansermet. Geological Museum, Lausanne, holotype specimen, n° 080126. Philippe Roth

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