Pseudomalachit z lokality Zadné Breziny pri Gemerskej Polome (Slovenská republika)

A new occurrence of pseudomalachite was recently discovered at the Zadné Breziny copper occurrence near Gemerská Poloma, Rožňava Co., Košice Region, Slovakia. It forms dark green rich coatings and crusts, which consist of individual hemispherical aggregates up to 7 mm in size. Pseudostalactites up to 6 mm in size were also rarely observed. Pseudomalachite occurs in fractures and cavities of the quartz gangue or in fractures of the wall rock. It is associated with malachite, cuprite and native copper. The refined unit-cell parameters (for the monoclinic space group P21/c) are a 4.4805(5) Å, b 5.7504(6) Å, c 17.045(2) Å, β 91.12(1)° and V 439.06(6) Å3. Except of dominant contents of Cu and P only minor amounts of Al (up to 0.04 apfu), Fe (up to 0.02 apfu), As (up to 0.07 apfu) and S (up to 0.01 apfu) were detected in studied samples of pseudomalachite from the Zadné Breziny occurrence.