Abstract Surface enrichment of silver-copper alloys is a current subject of research in archaeometry, while its origin in cultural heritage objects remains unclear. Due to their low penetration depth, surface techniques may give misleading results if the objects analyzed show this enrichment behavior. To study this effect, the surface and bulk composition of a group of Polish coins minted in the X-XI centuries during the early Piast dynasty were investigated using energy dispersive X-ray fluorescence (XRF) spectrometry and neutron activation analysis (NAA). A comparison of the results obtained using these two techniques permitted to classify the coins in two groups. The first group exhibited similar bulk and surface compositions, while coins in the second one showed silver surface enrichment. In addition, a correlation between silver and gold was observed after evaluating the analytical results providing a first step in the determination of silver provenance.

中文翻译：

---

中子活化分析 (NAA) 和能量色散 X 射线荧光 (XRF) 光谱法对皮亚斯特早期铸币进行无损分析的比较

摘要 银铜合金的表面富集是当前考古学的研究课题，但其在文化遗产中的起源尚不清楚。由于渗透深度低，如果分析的物体显示出这种富集行为，表面技术可能会给出误导性的结果。为了研究这种影响，使用能量色散 X 射线荧光 (XRF) 光谱法和中子活化分析 (NAA) 研究了一批在皮亚斯特王朝早期 X-XI 世纪铸造的波兰硬币的表面和整体成分。使用这两种技术获得的结果的比较允许将硬币分为两组。第一组表现出相似的体积和表面成分，而第二组中的硬币显示出银表面富集。此外，