Determination of impurities in antique silver objects for authentication by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)
Determination of impurities in antique silver objects for authentication by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)
复制标题
通过激光烧蚀电感耦合等离子体质谱 (LA-ICP-MS) 测定古董银器中的杂质以进行鉴定
DOI：
10.1039/a900073i
复制
发表时间：
1999
期刊：
影响因子：
--
通讯作者：
P. Lienemann
中科院分区：
文献类型：
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作者：
W. Devos;C. Moor;P. Lienemann
除了视觉特征之外，银合金中的微量元素和微量元素图案也是银古董真伪验证的一个不易操作的标准。用于分析贵银古董的分析方法不应明显损坏物体，并且应能够测定 ppm-0.5% 范围内的杂质。使用激光烧蚀电感耦合等离子体质谱 (LA-ICP-MS)，可以将可见损伤限制在可接受的最低限度。由于大多数古董银制品太大，无法放入普通的激光烧蚀单元中，因此使用了替代单元设计，可以对整个古董银制品进行直接、几乎无损的分析。该细胞被放置在待分析的物体上。然后通过单元底部的孔烧蚀微量的物体。这些 100 微米宽的陨石坑在古董银器上几乎是看不见的。测量了分析物 Zn、Cd、Sn、Sb、Au、Pb 和 Bi。将信号标准化为 Ag 信号，并使用银标准材料进行外部校准。对于大多数元素，均质银样品中标准化信号的凹坑间重复性低于 10% RSD (n=3)。检测限在亚 ppm 至 2 ppm 范围内。通过消化后比较 ICP-MS 测量和 X 射线荧光 (XRF) 测量验证了准确性。对八件古董银器（包括一件赝品）的分析说明了该方法的应用。
In addition to visual characteristics, a less manipulable criterion for authenticity verification of silver antiques is given by trace and minor element patterns in the silver alloy. The analytical method used to analyse precious silver antiques should not visibly damage the object and should enable the determination of impurities in the ppm-0.5% range. Using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), visible damage can be restricted to an acceptable minimum. Because most antique silver objects are too large to fit into a normal laser ablation cell, an alternative cell design was used that allows a direct, virtually non-destructive analysis of entire antique silver objects. This cell is placed upon the object to be analysed. A micro-amount of the object is then ablated through an aperture in the bottom of the cell. The 100 µm wide craters are almost invisible on an antique silver object. The analytes Zn, Cd, Sn, Sb, Au, Pb and Bi were measured. Signals were normalized to the Ag signal and silver standard materials were used for external calibration. The crater-to-crater repeatability of the normalized signals in a homogeneous silver sample was below 10% RSD (n=3) for most elements. Detection limits lie within the sub-ppm to 2 ppm range. The accuracy was validated with comparative ICP-MS measurements after digestion and with X-ray fluorescence (XRF) measurements. The analysis of eight antique silver objects, including one forgery, illustrates the application of the method.