Abstract The Neogene Central Slovakia Volcanic Field in the Carpathian arc contains various Au deposits, hosted by central zones of large andesite stratovolcanoes. Fluids involved in mineralization have been studied at three different types of deposit, mostly by fluid inclusion and stable isotope techniques. The Rozália mine in the Štiavnica stratovolcano hosts intermediate sulphidation-style Au–Ag epithermal mineralization in subhorizontal veins related to hydrothermal activity during an early stage of caldera collapse. Associated fluids of low salinity underwent extensive boiling at 280–330 °C on transition from suprahydrostatic towards hydrodynamic conditions at shallow depths ( c. 550 m) from fluids of mixed magmatic and meteoric origin. The Kremnica ore field hosts a large system of low sulphidation-style Au–Ag veins contemporaneous with rhyolite magmatism and situated on resurgent horst faults. Fluids were of low salinity, predominantly of meteoric origin, and showed gradual decrease in temperature along the system ( c. 270–140 °C) related to a decrease in erosion level from c. 500 to c. 50 m. The Biely Vrch Au-porphyry deposit in the Javorie stratovolcano is associated with quartz stockwork in diorite porphyry intrusion. The major type of ore-bearing fluid was high temperature magmatic vapour (720–<380 °C) accompanied by Fe-rich salt melt. Gold precipitated in a high-temperature but low-pressure subvolcanic environment. Supplementary material: Stable isotope data and fluid inclusion microthermometric data are available at http://www.geolsoc.org.uk/SUP18752 .

Abstract The Rozália mine is one of the youngest in the Štiavnica-Hodruša ore district. The mine was operated by the state company Rudné Bane until 1992, and since 1994 by the private company Slovenská Banská, s.r.o. Interestingly, three different types of ore have been extracted successively during the existence of this mine. Initial steps to mine Cu ores of the Rozália vein were taken in the year 1939; however, the war interrupted mining until 1948. Exploitation was finally restarted in 1951. In total 1,864,000 tons of copper ore was produced through 1990 with an average Cu content of 0.74 wt% (Fajbík, 1997). The vein was developed and exploited down to the 14 th level (+230 m above sea level, corresponding to a depth of 350 to 400 m below the surface). After exhaustion of the Cu ores of the Rozália vein, the richest parts of the stockwork and disseminated base-metal ores, located in the hanging wall of the Rozália vein on the 8 to 10 th levels, were exploited in 1991 — 1992. According to Kana (1997) from 1. 11. 1990 through 31. 12. 1991 a total of 62,137 tons of ore was mined with an average metal concentration of 1.31 % Pb, 1.59 % Zn and 0.34 % Cu. In January, 1992, underground exploration of newly discovered gold mineralization was started on the 14 th level of the Rozália mine. Exploration work was successful (Šály and Kámen, 1992; Šály et al., 1994) and exploitation began in 1993 and is still in progress. Today