Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original paper

Radana Vrtišková, Luboš Vrtiška, Jiří Sejkora, Zdeněk Dolníček, Jakub Trubač, Ladislav Strnad

Sn-rich phosphates, kintoreite and plumbogummite, from the Ratibořské Hory Ag-Pb-Zn deposit, Czech Republic

Journal of Geosciences, volume 69 (2024), issue 4, 213 - 224

DOI: http://doi.org/10.3190/jgeosci.398

Phosphates of the plumbogummite group (kintoreite and plumbogummite) with unusually high Sn contents have been discovered in a field in the area of reclaimed mine dumps at the abandoned Ag-Pb-Zn deposit Ratibořské Hory (South Bohemia Region, Czech Republic). These phosphates form very finely dispersed microscopic grains in the hydrothermal veins penetrating altered muscovite paragneisses in association with quartz, opal, pyromorphite, acanthite and more rarely galena, sphalerite, iodargyrite, imiterite, cuprite, mimetite, coronadite and unidentified Sn silicate. The studied Sn-rich phosphates can be divided into three groups: 1. Sn-rich kintoreite with the empirical formula (mean of the 14 point analyses) corresponds to Pb_1.05(Fe_2.51Sn_0.46Zn_0.06)_Σ3.03(PO₄)_1.55(PO₃OH)_0.45(OH)_6.00; 2. Sn-rich plumbogummite with empirical formula (mean of 6 analyses) Pb_1.14(Al_2.50Sn_0.52Fe_0.04)_Σ3.06(PO₄)_1.98(PO₃OH)_0.02(OH)_6.00; 3. (Sn,Al)-rich kintoreite with mean composition (calculated from 14 analyses) (Pb_0.95Ca_0.05)_Σ1.00(Fe_1.62Sn_0.90Al_0.62Zn_0.05)_Σ3.19(PO₄)_1.69(SiO₄)_0.21(AsO₄)_0.10(OH)_6.20. To date, no primary Sn minerals have been observed in the Ratibořské Hory ore deposit. Elevated Sn contents (up to 3040 ppm) in sphalerites from the Stará Vožice - Ratibořské Hory ore district, especially from the area with the occurrence of Sn-rich phosphates detected by La-ICP-MS during this research, probably indicate a primary source of Sn entering to the supergene processes.