Regional provenance assessment of Tang period turquoise from Xuewei Tomb No 1, Reshui Cemetery, China

Turquoise ornaments from Xuewei Tomb No. 1 (Reshui Cemetery, Qinghai) were analysed to evaluate procurement during the Tang period. Thirty-two specimens were screened by FTIR, 31 by Raman spectroscopy and 24 by LA–ICP–MS, generating 53 spot analyses. Most specimens consist of turquoise-group phases, with minor variscite and mixed turquoise–variscite domains. Microtextural features indicate supergene formation in porous, sediment-hosted environments. Geochemical comparison with available Qinghai–Gansu–Hami (QGH) reference data places the artefacts within the north-western comparative field and separates them from Hubei–Henan–Shaanxi sources, with the strongest affinity to the Gansu reference set. Because Qinghai and Gansu reference coverage remains limited, mine-level attribution is treated cautiously and most artefacts (15 of 24) remain unresolved (NOA) under open-set screening, reflecting the limits of reference coverage rather than positive evidence for a non-domestic source. Results support a tentative north-western affiliation and motivate expanded reference sampling and comparative testing.