Provenance of the gold of the Early Bronze Age Nebra Sky Disk, central Germany: geochemical characterization of natural gold from Cornwall

Abstract

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.

Early Cambodian gold and silver from Prohear: composition, trace elements and gilding

“…Usually e and also in most samples of the present study e tin is present as minor or trace element (Guerra et al, 1999;Brostoff et al, 2009) that indicates that the gold was extracted from a tin-bearing placer deposit (Dube, 2006). It seems to be an important element for the comparison of artefact gold with placer gold (Ehser et al, 2011). Most likely it enters the gold through joint panning of placer gold with cassiterite (SnO 2 ) and consequent melting under reducing conditions (Dube, 2006).…”

Trace Elements in Ancient Gold Products with PGE Microinclusions from Archaeological Sites of the Urals and North Black Sea Region: LA–ICP–MS Data

“…This difference probably relates to the influence that gold refinement and processing have on trace element concentrations (e.g., Ehser et al . and references therein). Among the various refinement techniques, cupellation—which has been known since the Early Bronze Age (e.g., Pernicka et al .…”

“…Because the concentrations of other possible trace elements are typically below the detection limit of microprobes, laser ablation with inductively coupled plasma mass spectrometry (LA–ICP–MS) has recently become a popular method of analysing the trace element composition of ancient gold products (e.g., Ehser et al . ; Guerra et al . ; Pernicka ).…”

Morgawr: an experimental Bronze Age-type sewn-plank craft based on the Ferriby boats

“…This extraordinary object, which shows a representation of the heavenly bodies, perhaps for astronomical predictions, is made of bronze with gold inlays. Analysis now shows that while the copper comes from the Austrian Alps, the tin and gold in all likelihood come from Cornwall (Haustein et al ., ; Ehser et al ., ). These facts confirm what the isolated artefacts such as the Rillaton cup have long suggested: that Cornwall was part of a large‐scale and long‐distance trade network, in existence since at least the Early Bronze Age.…”