The degassing of basic silicate minerals (olivines, pyroxenes, plagioclases) that make up mantle rocks similar in chemical composition to lunar mare basalts has been studied. A setup specially designed for these tasks was used, previously used in the study of chondrite degassing. The results of experimental studies on stepwise heating (without accumulation) with determination of the composition of released gases using gas chromatography methods in the temperature range from 200 to 1000 degrees C are presented. The composition of the released gases was compared with the fugacity of oxygen in olivines. Raman and IR spectra of both the original minerals and minerals after isothermal annealing at various temperatures were obtained. Based on them, the course of thermal transformation of the crystalline structure of minerals was traced and estimates of their stability were obtained. The composition of silicate minerals was compared with samples of lunar soil delivered by the Chinese space mission Chang'e-5.