The study is aimed at a more detailed determination of the thermal properties of Baikal region sands and establishment of their dependence on geological and mineralogical characteristics in order to assess the possibility of using this raw material in the food industry. The objects of the study are sands sampled on the southwestern coast of Lake Baikal. The subject of the study is the mineralogical composition of sand, its grain size composition and heat capacity. The mineral composition of sand samples and their crystal structure were studied using the method of X-ray phase analysis. A standard sieve analysis method was used for granulometric estimation of sands. The average heat capacity of sand samples was determined by the mixing method. Based on the analysis of the obtained X-ray diffraction patterns, the mineralogical composition of the studied samples was determined. It was found that quartz predominates in their composition since its percentage in samples amounts to 40–60 %. The proportion of such minerals as albite and anorthoclase is 15–30 % in different samples. Less than 5 % in each sample accounts for dickite and indialite. The presence of the mineral of anthophyllite has been found only in one sample in the amount of about 9 %. The results of granulometric composition determination show that a fraction, which accounts for 70–90 %, can be isolated in most samples. The sample from the town of Slyudyanka was the only one where the fractions of different sizes were present in approximately equal amounts. For this sample, the dependence of heat capacity on the grain size was determined. In other samples, the difference in certain heat capacity values correlated well with their mineralogical composition. The results of the conducted studies and their analysis allow to conclude that Slyudyanka and Baikalsk sands are the most attractive sands in terms of high heat capacity. The sand with the grain size from 0.125 to 0.25 mm is found to be the most suitable for the use as a thermal storage medium. This fraction is predominant in the sand of the town of Baikalsk.
