Wilson P F, Smith M P, Hay J, Warnett J M, Attridge A, Williams M A
1Warwick Manufacturing Group (WMG)-University of Warwick, Coventry, UK.
2Oxford University Museum of Natural History (OUMNH)-University of Oxford, Oxford, UK.
Herit Sci. 2018;6(1):58. doi: 10.1186/s40494-018-0223-0. Epub 2018 Oct 3.
This paper demonstrates the combined use of X-ray computed tomography (XCT), energy dispersive X-ray spectroscopy (EDX) and X-ray fluorescence (XRF) to evaluate the conservational history of the dentary (lower jaw) of Mantell, 1827, the first scientifically described dinosaur. Previous analysis using XCT revealed that the specimen had undergone at least two phases of repair using two different kinds of plaster, although their composition remained undetermined. Additional chemical analysis using EDX and XRF has allowed the determination of the composition of these unidentified plasters, revealing that they are of similar composition, composed dominantly of 'plaster of Paris' mixed with quartz sand and calcite, potentially from the matrix material of the Stonesfield Slate, with the trace presence of chlorine. One of the plasters unusually contains the pigment minium (naturally occurring lead tetroxide; Pb PbO) whilst the other seems to have an additional coating of barium hydroxide (Ba(OH)), indicating that these likely represent two separate stages of repair. The potential of this combined approach for evaluating problematic museum objects for conservation is further discussed as is its usage in cultural heritage today.
本文展示了如何联合使用X射线计算机断层扫描（XCT）、能量色散X射线光谱（EDX）和X射线荧光（XRF）来评估1827年曼特尔首次科学描述的恐龙——齿骨（下颌骨）的保存历史。此前使用XCT的分析表明，该标本至少经历了两个阶段的修复，使用了两种不同的石膏，但其成分仍未确定。使用EDX和XRF进行的额外化学分析确定了这些不明石膏的成分，结果显示它们成分相似，主要由“巴黎石膏”与石英砂和方解石混合而成，可能来自斯通菲尔德板岩的基质材料，并含有微量的氯。其中一种石膏异常地含有颜料铅丹（天然存在的四氧化三铅；Pb₂PbO₄），而另一种似乎还有一层额外的氢氧化钡涂层（Ba(OH)₂），这表明它们可能代表了两个不同的修复阶段。本文还进一步讨论了这种联合方法在评估有问题的博物馆藏品以进行保护方面的潜力，以及它如今在文化遗产中的应用。
