The In-Ga-Sb association of the post-Variscan Zn-Pb-Ag vein deposit at Lautenthal, Upper Harz Mountains, Germany: sphalerite mineral chemistry

• DOI: 10.1007/s00126-024-01261-8
• Publication Date: 2024-04-13T04:01:27Z
• Authors: Torsten Graupner; Sören Henning; Simon Goldmann; Sebastian Fuchs; Klaus Stedingk; Wilfried Liessmann; Sven Birkenfeld
• Keywords: Bornite; Overprinting

Abstract The Lautenthal sphalerite-galena vein deposit is part of the world-class Upper Harz Pb-Zn-Ag district in uplift block Paleozoic Variscan fold belt Germany. Its sphalerite-dominated mineral association was studied using bulk-ore chemistry, electron probe microanalysis, and laser ablation-ICP-mass spectrometry. Gallium locally In are main high-tech-relevant trace elements hosted by sphalerite, with up to 150 ppm Ga 380 hand-picked sphalerite samples (mean In/Zn, 0.70 × 10 −3 ). Ore concentrates (≤ 50 kg) contain 65 109 0.36 Accessory Fe-Co-rich gersdorffite-1 occurs earlier quartz-sulfide ore stage Sb-rich gersdorffite-2 later carbonate-sulfide stage. Enrichment patterns either defined overprinting textures Fe-richer sphalerite-1 stage, or relate primary growth zoning Fe-poor sphalerite-2 Using geothermometer GGIMFis, formation temperatures (median) were estimated at ~ 230 °C for orebody 175 Bromberg orebody, which may indicate lateral T-zonation Sphalerite-2 data 185 (median). Copper-bearing brines assumed 250 initiated replacement In-poor chalcopyrite remobilization Zn elements. Indium-rich associated calcite fine-grained galena. A direct spatial temporal link a magmatic-hydrothermal system unlikely, contrasts In-rich epithermal tin-polymetallic deposits worldwide.