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This archaeometric study aims at characterizing the archaeological finds belonging to the lithic industry from La Calvera rock shelter (Camaleño, Cantabria) and at hypothesizing the possible provenance of each material. The site, located in the mountainous area of Picos de Europa National Park (more than 1000 m a.s.l.) close to the megalithic complex of Peña Oviedo, is characterized by the presence of hearths and charcoal remains, ancient pottery, and a rich lithic assemblage composed of siliceous rocks dating back to >8000 BP and linked to the first Holocene occupations of the Cantabrian Mountains. For the study of the rock shelter's lithic assemblage, a multi-analytical approach was used: SEM-EDS and XRD analyses were performed to define the microtextural characteristics of samples and to identify the amorphous/crystalline phases; physical and mechanical tests were conducted to define the petrophysical properties (density, porosity, imbibition and saturation indexes, mechanical strength) of the samples. Preliminary data of chemical compositions, obtained by portable XRF, are also presented. The results show that the different siliceous materials (quartzite, cherts, hyaline quartz) can be distinguished through the basic analytical techniques used here. In addition, most of the archaeological samples have mineralogical and petrographic features similar to the natural samples coming from nearby outcrops, corroborating the hypothesis of a local material supply. The presence of local sources of useful raw materials could have favoured the site's occupation. Finally, the diverse compositional and textural feature of the analysed materials result in different mechanical properties (porosity, density, hardness, workability), so they likely had different uses and technical functions. [ABSTRACT FROM AUTHOR]

Soluble salts are compounds found inside ornamental rocks and building stones exposed to atmospheric agents in environments rich in alkaline metal ions, such as sodium and potassium. The damage induced by their crystallization in those materials, used to build monuments and architectural structures of great importance, is an unsolved problem. Sodium sulfate is one of the most common and harmful salt found in these constructions. In this work, we studied the resistance through time to the wet-drying cycles of some natural stones (calcarenites, marbles, and sandstones) that have been utilized in the historical architecture in Italy. Samples were freshly cut and thermally aged to simulate increasing decay. Induced porosity in the thermally degraded samples was high in calcarenites, medium in marbles, and low in sandstones. Specimens subjected to artificial thermal aging lost a major percentage of mass compared to the non-weathered ones, when affected by the crystallization of soluble salts. With this study, we have observed that samples subjected to different wetting and drying cycles degrade faster due to the action of soluble salts, compared to samples that are not subjected to these cycles. [ABSTRACT FROM AUTHOR]

Trace element analysis of sediments from archaeological sites is a valuable method to investigate the anthropic impact and obtain information on the functions of different areas and changes in human activities. One of the most used and effective techniques to carry out this kind of analysis is inductively coupled plasma–mass spectrometry. This technique needs a previous dissolution of the sample by acid attack, but the development of the best method is still a discussed issue. In the present work, total and partial digestion methods were carried out in sediment samples of Cueva de la Cocina (Dos Aguas, Spain), and trace elements were measured and statistically compared. Major elements, soil organic matter amount, and pH data were used to evaluate the main drivers of trace element contents. The differences between the results from the two methods were highlighted. Total digestion is more effective for aluminosilicates and heavy minerals, although the partial digestion results suggested that, in most cases, the difference between the two methods is irrelevant for archaeological interpretations. Furthermore, in some cases, the total digestion of the mineral phases related to the geological contribution could mask the anthropic elemental signals. [ABSTRACT FROM AUTHOR]

The quarrying of marble and its processing to produce building materials often generates a negative impact on the environment. In the Apuan Alps marble district, a renowned quarrying area in Italy since ancient times, the aquatic pollution of water bodies, caused by the presence of marble waste in the form of powder or sludge, represents a significant and current environmental problem. Depending on the different national and international regulations on waste management, the marble waste can be classified as a special non-hazardous industrial waste. If marble waste has been managed according to environmental international and national laws, it can be reused as a by-product. For this, the present work aims to evaluate the reuse of marble waste as a material in replacement for cement for producing mortars. Subsequently, the mechanical and physical tests were carried out to evaluate the specific properties of the obtained materials during and after the curing time. The results showed that replacement of cement into mortars by marble waste always causes a decrease of mechanical properties, with still acceptable values for many applications up to a substitution of less than 25%. From the collected data, the use of marble waste in the production of cement mortars represents an adequate and sustainable destination of this by-product. [ABSTRACT FROM AUTHOR]

This study deals with the mortars and subordinately rocks collected from the archaeological site of Cap de Forma, that is a "Bien de Interés Cultural" located on a cape along the southeastern coast of Menorca (Balearic Islands, Spain). Cap de Forma consists of different structures belonging to different periods and civilization phases: a fortified settlement of Talaiotic age, built in cyclopean technique and including three rooms and a rainwater cistern; a nearby necropolis of tombs (cuevas) excavated into the cliff; a more recent site occupancy testified by plastering of the cistern; a house-fort (pecheña casa-quartel), a lookout point of the 17th–18th century. Compositional features and mineralogy of mortars and rocks were investigated by optical microscopy and X-ray diffraction. Physical properties (density, porosity, water saturation and water saturation coefficients and mechanical strength) were also determined. This work is aimed at characterizing these archaeologic remains to understand the building technique, the choice of raw materials and possibly their provenance, taking into account the age and civilization they belong to. Results indicate that cocciopesto-rich mortars were used in the cistern watertight and other ancient structures linking from a Roman age. The cocciopesto seems to derive from local pottery even if some evidence would suggest the contrary, whereas the source of the binder is definitely the local Mg-rich limestone. The house-fort was plastered with gypsum-based mortars in the 17th–18th century. The most likely source of raw gypsum was the island of Mallorca where some quarries were opened in the same period. Mechanical and physical tests reveal a strong state of decay that requires conservation actions. This work sheds light on a poorly studied monument, better constraining the different phases of its occupation. Some interesting questions, such as the cocciopesto provenance, are still open. [ABSTRACT FROM AUTHOR]