UDK 553.21:553.532 Glass-Ceramics Obtained by the Crystallization of Basalt

The possibility to obtain glass-ceramics from basalt from the locality on Vrelo (Kopaonik mt.) is shown in this paper. The parent rock was ground to fraction-0.4 +0.1 mm, and then melted at 1250- 1300oC. The crystallization melted bazaltic glass at 950 °C during the time interval of 3 hours caused synthesis of a glass-ceramic material with a microstructure that has excellent mechanical properties according to the determined dynamic modulus of elasticity and uniaxial compresive strength. The phase composition of the obtained glass ceramic material was determined by XRPD using Rietveld refinement and SEM. Two phases were found: pyroxene which corresponds to omphacite of the composition (Na0.199 K0.180 Ca0.471 Mg0.249)1.1(Mg0.271Fe0.299Al0.430)1.0(Si1.704Ti0.046Al0.250)2.0O6 and glass with an approximate relationship 69:31