Institute of Geology, Karelian Research Center, Russian Academy of Sciences, Petrozavodsk, Russia:

V. P. Ilina, Senior Researcher, Candidate of Engineering Sciences, Ilyina@igkrc.ru

Soapstone is a unique natural material applicable in different productions owing to its valuable properties such as alkali and acid resistance, refractoriness, heat capacity; moreover, soapstone is machinable. Russia’s Shabrovsky Talc Plant produces ground talc–magnesite and manufactures talc–magnesite bricks. In Finland, the world’s known companies Tulikivi (Verikallio, Kivikangas deposits) and Nunna Uuni Oy (MammuttiStone deposit) produce soapstone to make fireplaces and, recently, floor. A great portion of soapstone fields occurs near the Lake Segozero in Medvezhyegorsky district, including the Kallievo-Murenvaara deposit. For the best part of soapstone monoliths have been extracted, in focus is feasibility of using enclosing rocks of metapikrite as a material for the manufacture of bakeovens and fireplaces. The thermophysical properties of metapikrite and talc–chlorite schist are studied and compared with the Finland soapstone. It is found that metapikrite rocks have low indexes of thermal expansion at 20–900 °С, heating capacity from 6 to 12 temperature changes at 20–950 °С and higher compression strength as against talc–chlorite schist and soapstone from other deposits.

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