Abstract The petrophysical characteristics of a building stone used in the city of Pavia, northern Italy, are analysed in the light of stone conservation through the application of water repellent and consolidant products. The research focuses on the modification of petrophysical properties as a function of the applied products, and on the critical assessment of the performances of fluorinated and siloxane resins as a function of the variable nature of the same lithotype. The studied material is a calcareous sandstone (Mt Arzolo Sandstone), Late Miocene–Early Pliocene in age, extensively employed as a building material during the 11th and 12th centuries. Experimental investigations on samples from historic quarries were performed before and after application of treatments: i.e. petrographical and fabric analyses; ultrasonic measurements; mercury porosimetry; abrasion resistance measurements; contact angle measurements; capillary and low-pressure water absorptions; water vapour permeability; and colour measurements. Two main lithotypes of Mt Arzolo Sandstone were recognized according to their petrophysical features: the open porosity being similar, differences exist concerning their fabric. These differences influence the physical–mechanical properties of the material and consequently the performances of the applied products. In particular, the difficulties in penetration of products when sandstone of smaller pore size is treated can lead to a significant reduction of the overall performances, which is more evident for products containing organic solvent with high molecular weight.

Abstract The paper illustrates the results of an archaeometric project on the raw material characterization of some collections of prehistoric polished stone tools, dated from the Early Neolithic to the Bronze Age, from sites located in Northern Italy. The petrographic analyses (surface and thin-section microscopy, X-ray powder diffraction, scanning electron microscopy–energy–dispersive spectrometry, X-ray fluorescence, atomic absorption spectrometry) revealed a raw material circulation network involving the whole of Northern Italy. Here occur the outcrops of high-pressure (HP) meta-ophiolites, which were widely utilized from the Early Neolithic onwards for the manufacture of polished cutting-edged tools, which are represented by axes, adzes and chisels. Other raw materials, such as serpentinites, seem to have been preferred for the production of other types of artefacts, including stone rings used as bracelets. The analyses revealed that the prehistoric polished stone artefacts were made from uncommon lithologies such as Alpine eclogites, jades and other HP meta-ophiolites. These rocks were exploited from primary and secondary sources, mainly located in Piedmont, the Aosta Valley and Liguria. During the Neolithic these lithologies are the dominant raw material for the polished stone tools in Northern Italy and southeastern France. In the same period, in other European countries the same lithologies occur less frequently as axe or adze blades; in NW Europe they were frequently used for manufacturing long ceremonial axes, which have a typology that does not appear to belong to the Italian tradition.