Petrographic and geochemical analyses to characterise the source of built historical natural stones - a case study of the volcanic stones from historical quarries and Baoguosi Temple in the city of Ningbo, China.

Abstract

Characterising and sourcing natural stones are essential for not only understanding the historical information carried by heritage buildings and cultural heritage sites, but also providing necessary data for restoration and conservations. Petrographic analyses by polarised microscopy, along with the integrated chemical data acquired by inductively coupled plasma-mass spectrometry (ICP-MS) and X-ray diffraction (XRD) analysis, allowed us to ascertain the compositions of stone materials. In this paper it is applied on samples collected from quarries of "three famous stones (Meiyuanshi-, Xiaoxishi-, and Dayinshi-stone)" in Ningbo and from the Sumeru platform in the main hall of Baoguosi Temple (Ningbo, Zhejiang, China). Comparison of petrographic features, major and trace elements of the stones studied indicated that they are all tuffs but of different characteristics and origin. Moreover, we were able to confirm that the Sumeru platform in Baoguosi is made of Meiyuanshi-stone. The results have demonstrated the suitability of the approach and present a practicable solution for other stone buildings.