Mimetite and Sb-rich segnitite from the Zlatá Idka Ag-Au-Sb deposit, Spišsko-gemerské rudohorie Mts., Slovakia

A new occurrence of mimetite and Sb-rich segnitite was discovered at the dump of the Najvyšší Štefan adit at the Zlatá Idka Ag-Au-Sb deposit near Zlatá Idka, Spišsko-gemerské rudohorie Mts., Košice-okolie Co., Košice Region, Slovakia. Mimetite occurs as white to colourless prismatic crystals up 2.5 mm in size, developed on fractures or in cavities of quartz gangue. Its average (n = 15) empirical formula (based on sum of As+P+S = 3 apfu) is Pb4.99[(AsO4)2.75(PO4)0.22 (SO4)0.03]Σ3.00Cl1.12. Sb-rich segnitite forms greenish-yellow botryoidal microcrystalline crusts, which are partly covering or replacing crystals of mimetite. Significant contents of Sb (ranging from 0.15 to 0.34 apfu) substituting for Fe3+ on B-site were observed in studied sample. The average (n = 12) empirical formula of segnitite from the Zlatá Idka-Ag-Au-Sb deposit (based on sum of As+P+Si+S = 2 apfu) is Pb1.09(Fe2.73Sb0.22Al0.02Zn0.01)Σ2.98[(AsO4)1.08(AsO3OH)0.56(PO4)0.27 (SO4)0.07(SiO2)0.02]Σ2.00(OH)6.17.