Provenance analysis of human cremations by 87Sr/86Sr isotopic ratios: migration into an Iron Age mining region in North-Rhine Westphalia

The Siegerland (North-Rhine Westphalia, FRG) is famous for its early mining industry and ore exploitation. The archaeological context of cremated burials as well as grave goods indicate parallels to today's Wetterau (Hesse), suggesting migration into the Siegerland. After morphological examination of the cremations augmented by a histological age-at-death determination, provenance analysis by use of stable strontium isotope analysis was carried out. 60 individuals from the burial mound at Netphen-Deuz in the Siegerland were available for anthropological examination. The ⁸⁷Sr/⁸⁶Sr isotopic ratio was measured in 29 dentine and 15 bone samples. At least 19 individuals exhibited a non-local isotopic signal which was compatible with a provenance from the Wetterau region. Since ⁸⁷Sr/⁸⁶Sr isotopic ratios in the bioapatite are thermally stable, provenance analysis of cremated finds is thus possible, whereby a testable archaeological hypothesis is prerequisite. Histological examination of cremated bones proved indispensable for the age-at-death estimation.