مطالعه میراث فرهنگی: تکنیک های میکرو تخریبی برای تشخیص مواد معدنی خاک رس در سطح ساختمان های تاریخی

In this paper we report on the application of microdestructive analytical techniques in order to identify the presence and the origin of clay minerals found on the surfaces of several historic buildings located in the Apulia region (Southern Italy). Optical and SEM observations, along with EDS microanalyses, and FTIR analyses were performed. The microdestructive character of these techniques made it possible to carry out the analyses on the same specimen, thus reducing the sampling. XRD analyses were also performed to confirm the presence of clay minerals. The complementary analytical findings were helpful in most cases in establishing the real origin of the clay minerals; the detection of organic materials arising from man-made treatments allowed to identify clays as pigments. However, in some cases the uncertainty remained between ochre, intentionally employed, and soil–dust deposition.