The X-ray powder diffraction is used to characterize solid samples. Using this method, 14 samples of soil and rock minerals taken from various places around Ivančna Gorica, were analysed. After preparing the samples and measuring diffractograms, I performed a qualitative and quantitative analysis for each sample. A qualitative analysis was done using the Crystalographica Search Match program and a collection of powder diffractograms (PDF-2). The X-ray powder diffraction pattern is characteristic for a particular solid and thus also for minerals. Therefore, based on the matching of reflections on the diffractogram of the standards from the PDF-2 database with those on diffractogram of the sample, I was able to identify which minerals are present in the samples. I also confirmed the content of the identified phases with a quantitative analysis using the TOPAS program, where I determined the mass fractions of the identified minerals using the Rietveld method.
I found that carbonates and silicates occur most often in the samples, both in terms of content and mass fraction in the sample. Sulphides and oxides (except quartz) occur rarely and in very small quantities. The rock samples contain predominantly dolomite and calcite, which means they have a carbonate composition. Stone in sample no. 3 was different in appearance and composition and, in addition to carbonates, also contains sulphides, oxides and silicates. The soil and clay samples all contained considerable amount of quartz as well as the silicate minerals muscovite and clinochlore and, except for sample 1, also dolomite and, in some cases, calcite. The results of the sample analysis match with the data in the geological map of Slovenia for the region around Ivančna Gorica.
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