Archaeometric perspective on the emergence of brass north of the Alps around the turn of the Era

Abstract

Ancient brass (aurichalcum) was a valued commodity in the Antiquity, notably because of its gold-like appearance. After mastering brass fabrication using the cementation procedure in the first century BC in the Mediterranean, this material became widely used by the Romans for coins, jewellery and other artefacts. Because of its visual qualities, it is believed that since this period, brass played an important role in diplomatic and economic contacts with indigenous communities, notably Celtic and Germanic tribes north of Danube and west of Rhine. To test this hypothesis, we performed for the first time the advanced statistical multivariate analysis based on chemical composition and lead isotope systematics, coupled with informed typo-chronological categorisation, of a suite of late Iron Age and Early Roman period (first century BC – first century AD) brass and other copper-alloy artefacts from the territory of Bohemia. In order to to discuss their provenance, the results were compared to known contemporary sources of material. The new results for brass artefacts from this early phase of the massive occurrence of Roman aurichalcum in the Barbarian territories point to the ore deposits in the western Mediterranean or the Massif Central area in Gaul, consistent with historical events. These new findings underscore the great economic and political importance of the new and rich mineral resources in the Transalpine Gaul acquired due to Caesar's military campaigns.

Local supply and long-distance imports: New evidence for the origin of brass, copper and lead at Helgö

“…The Helgö brasses indicate access to fresh brass unrelated to the metal available earlier. Isotopically, the core group of six objects, from BG 3, 4 and 5 (excluding, momentarily, the two outliers) are inconsistent with published data on western Roman brasses, which mainly relates to brass artefacts from western or central Europe linked to zinc ore from the Massif Central (Hanel & Bode 2016;Bursak et al 2022;Merkel 2021a), northern Italy (Merkel 2021b) and the Eifel region of Germany (Merkel 2021a; 2021b) (fig. 10).…”

A long‐distance copper alloy trade to the North Eastern Baltic during the late pre‐Roman and Roman Iron Age (250 BCE–450 CE) explored with lead isotope MC‐ICP‐MS

“…Following Pliny and Biringuccio's suggestions that zinc ore was mined in the Alpine region of Southern Europe, Merkel tentatively concluded that zinc ores mined in the Alpine region of northern Italy could indeed be a source for Roman brass. Further research by Bursák et al (2022) on a group of first century BCE to first century CE Cu alloy artefacts also suggested that ore deposits in the Massif Central area of southern France could be the source. Also, that recycling activities during this time did not overly affect the geochemical properties of the brass entering Barbaricum due to a high degree of homogeneity.…”

“…This change is partly characterized by a large increase in both the quantities and variation of Cu alloy grave goods found in the communal cemeteries in north‐eastern Estonia, much of which is typologically identical to, or at least stylistically influenced by, objects found much closer to the Roman world. It is thought that the metal‐producing regions of Southern Europe were largely under Roman control by this time, therefore much Cu alloy in the form of finished goods and scrap metal could have been finding its way to the North Eastern Baltic via Germania and the Vistula River route (Bursák et al, 2022; Lang, 2007; Roxburgh & Olli, 2019). But again, other sources of Cu alloy reaching the North Eastern Baltic cannot be ruled out.…”