A characterisation study of ignimbrites of Tenerife Island employed as building stone

Abstract

The objective of this study is to evaluate the petrophysical properties of four ignimbrites employed as dimension stones. The natural stone under study is produced in Tenerife Island (Spain) under the commercial brand name of Piedra Chasnera and are differentiated according to their chromatic variety into: brown, violet, grey and green. To assess the suitability for feasible applications, it is essential to have a comprehensive knowledge of its properties. In this respect, mineralogical, petrographic and chemical properties were obtained by X-ray diffraction (XRD), polarisation microscopy (POM) and X-ray fluorescence (XRF). According to the procedure described in the standardised methods, apparent density, open porosity, water absorption at atmospheric pressure, water absorption coefficient by capillary and ultrasound propagation velocity were measured. The four variants of ignimbrites were analysed and classified according to the results obtained. It was found that the properties vary depending on the depth of the stratigraphic volcanic level from which the stone is extracted. From the review of the published data, it can be seen that the test results are within the expected values for this lithotype. A comparison was also made with other types of dimensional stones. The correlation analysis shows that there is a high degree of correlation between the physical properties studied.