Basalt fibers have recently come into the spotlight due to their superior physical and chemical properties, which rank only below expensive carbon and silicon carbide fibers. The suitability of raw material for basalt fiber production is mainly determined by the mineral composition and crystallization properties of basalt melts. In this article, we present the results of integrated petrographic and mineralogical analyses of melanocratic basalts from the Southern Urals, in order to assess their suitability for the production of high quality basalt fibers. The low acidity and viscosity parameters indicate the possibility of producing brittle fibers with poor chemical resistance. Moreover, the refractory impurities decrease the quality of products made from these fibers. However, acceptable insulation properties are exhibited by the melanocratic basalts and therefore their significance in the construction industry is still high.