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The Early Bronze Age Nebra Sky Disk, central Germany, comprises different types of gold inlays which have been plated and punched onto a bronze disk in three phases. The present study aims at provenancing the gold, used for the first phase, which includes gold sheets in the shape of a sun or full moon, a crescent-shaped moon, and 32 stars. The geochemical composition, determined by LA-ICP-MS, of one fragment of the sun sheet is compared with 66 native gold particles from six placer deposits and one lode gold deposit in Cornwall. The focus on Cornish gold deposits is based on results of previous provenance and tin isotope studies. The geochemical survey is performed using distinctive geochemical tracers (e.g., Co, Ni, Cu, Ru, Pd, Ag, Sn, Sb, Ir, and Pt) which are characterized by high stability during geological and metallurgical processes. For Cornwall, the Carnon gold placers at the localities Devoran and Feock show different variations in Co, Ni, Pd, Ag, Sn, and Sb which correlate with the variation found in the gold from the sun sheet when mixed. This mixture would have been easily possible as both localities are located about three km apart from each other. Similar geochemical comparisons with natural gold from central and southeastern Europe, carried out in a previous provenance study, showed no similarity with the sun sheet. Differences in Cu and Pt contents between the Carnon gold placers and the sun sheet, which have also been detected for the previously studied gold deposits, question the relevance of mineral (micro) inclusions and accretions or unintended contamination with heavy minerals during processing. The results on the gold further led to the comparison of 18 Cornish copper ores with the bronze of the Nebra hoard using lead isotope ratios, which showed no correlation, excluding Cornwall as copper source. With the gold of the first phase of the Nebra Sky Disk being likely to originate from Cornwall, substantial metal trade from the British Isles towards central Germany during the Early Bronze Age must be assumed.

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The Skorpion zinc deposit in southwestern Namibia comprises a significant nonsulfide orebody (24.6 Mt at 10.6% Zn) and subordinate amounts of primary base metal sulfide mineralization, which structurally underlies the nonsulfide ores at depth. The host rocks of the blind, nonsulfide orebody and relict sulfide mineralization consist of a mixed volcano-sedimentary sequence of Neoproterozoic age that has formed in an initial continental rift system between the Kalahari cratonic province and the Rio de la Plata cratonic province. The metavolcanic and subvolcanic rocks display a distinct bimodal geochemical composition of within-plate affinity and have been emplaced under an extensional crustal regime. Zircons from a rhyolitic vesicular flow, extruded approximately contemporaneously with the volcanic-hosted sulfide mineralization, have been dated by SHRIMP U-Pb analysis and yield an age of 751.9 ± 5.5 Ma.The basin that hosts the Skorpion deposit has been shaped by horst and (half-)graben tectonics, which also controlled the sedimentary deposition of siliciclastic and carbonate sediments within both shallow and deeper water environments. The rock sequence was affected by a major tectono-metamorphic event the Pan African-Brasiliano orogeny at approximately 550 to 545 Ma. Metamorphism reached uppermost greenschist to lowermost amphibolite facies, and the complex deformational style of the region is the result of intense faulting, folding, and thrusting.The Skorpion orebody is hosted by arkosic metaarenites and subordinately by volcaniclastic metasedimentary rocks. It is irregularly shaped, transgressive to sedimentary layering, and has a relatively flat top, which is covered by a blanket of unmineralized overburden consisting of calcrete, boulder beds and recent sand dunes. At depth, the orebody has a relatively sharp contact with a barren marble unit on the east and south and a more gradational boundary within the siliciclastic host rocks on the west and north. The nonsulfide ore minerals comprise predominantly sauconite (Zn smectite), substantial amounts of hemimorphite and smithsonite, and subordinate amounts of scholzite, tarbuttite, atacamite, hydrozincite, and hetearolite. The ore minerals are mainly euhedral and subhedral crystals and occur as open space fillings in intergranular voids, fractures, and breccias and as replacements of feldspar and mica. The metasedimentary host rocks of the nonsulfide ore contain abundant iron hydroxide pseudomorphs after disseminated sulfides and stringers and after rare semimassive stratiform layers of sulfides. Gossanous, manganese and iron hydroxide-rich, siliciclastic, metasedimentary rocks are common in the western and northwestern vicinity of the nonsulfide orebody. Alteration of the supergene mineralized host rocks includes removal of calcite cement and the breakdown of detrital albite-rich plagioclase and of minor orthoclase. Local alteration phenomena also include silicification and rare secondary barite, both a result of the alteration and breakdown of feldspar.Minor base...