Abstract:
In this study, 160 silver-copper alloy denarii and antoniniani from the 3rd century A.D. were studied to obtain their overall chemical composition. The approach used for their characterisation is based on a combination of physical, chemical, and chemometric techniques. The aim is to identify and quantify major and trace elements in Roman silver-copper coins in order to assess changes in composition and to confirm the devaluation of the currency. After a first cataloguing step, μ-EDXRF and SEM-EDX techniques were performed to identify the elements on the coins’ surface. A micro-destructive sampling method was employed on a representative sample of the coins to quantify the elements present in the bulk. The powder obtained from drilling 12 coins (keeping the two categories of coins separate) was dissolved in an acidic medium; heated and sonicated to facilitate dissolution; and then analysed by ICP-AES and ICP-MS. The two currencies had different average alloy percentages; in particular, the % difference of Ag was about 8%. The other elements were found in concentrations <1 wt%. Of these, the element highest in concentration were Pb and Sn, which is in agreement with the literature. The multivariate analysis performed on the data acquired revealed two groups of coins, corresponding to the two currencies.
摘要:
在这项研究中,研究了公元3世纪的160种银铜合金denarii和antoniniani,以获得其整体化学成分。用于表征它们的方法是基于物理,化学,和化学计量学技术。目的是识别和量化罗马银铜币中的主要和微量元素,以评估成分的变化并确认货币贬值。在第一个编目步骤之后,进行了μ-EDXRF和SEM-EDX技术来识别硬币表面上的元素。在硬币的代表性样品上采用了微破坏性采样方法,以量化散装中存在的元素。将从钻取12个硬币(将两类硬币分开)获得的粉末溶解在酸性介质中;加热并超声处理以促进溶解;然后通过ICP-AES和ICP-MS进行分析。两种货币的平均合金百分比不同;特别是,Ag的%差异约为8%。其他元素的浓度为<1重量%。其中,浓度最高的元素是Pb和Sn,这与文献一致。对获得的数据进行的多变量分析显示两组硬币,对应于两种货币。