Aggregate of brilliant, little reddish, fragmented dufrénoysite crystals. They are arranged in a cavity of the dolomite matrix, along with pyrite. Dufrénoysite belongs to the sartorite group and has a Lengenbach type locality.

Rich group of needle to fibrous like dufrénoysite crystals, brilliant and disposed in a vug (12x7 mm) in the dolomite matrix. Dufrénoysite is now a member of sartorite group. With the FGL (Forschungsgemeinschaft Lengenbach) label L-10-4404 and from the Type Locality.

Small group of very brilliant seligmannite crystals, like mirrors, gray to dark brown color. They show well defined faces and edges. Accompanied by needle-like crystals of dufrénoysite, with fibrous appearance and almost black color, interpenetrating with seligmannite. A premium quality specimen for systematic collectors. BOTH SPECIES have the type locality in Lengenbach.
Code: LB 779 (1999)

A really interesting specimen of this uncommon sulphosalt. It presents elongated crystals, one with terminal faces, metallic luster and it is accompanied by brilliant realgar red crystals, some of them grew on sartorite. On the LGB dolomite matrix with pyrite. From this classic Swiss locality, type locality for the species.
Code: L 23.729 (1992)