A fabric is formed from yarn comprised of inorganic filaments coated with rayon. Specifically, the inorganic filaments are spun from a melt of volcanic black rock and are comprised of calcium oxide, magnesium oxide, potassium oxide, aluminum oxide, iron oxide, silicon dioxide, titanium dioxide, sodium oxide, and boron. As a result of its composition, the fabric is temperature resistant and lightweight, yet strong. Preferably, the fabric exhibits a melting point between 1500.degree. C. and 1650.degree. C., a working range of -130.degree. C. to 700.degree. C., a density of 1.6 g/cc, a surface density between 160 g/m.sup.2 and 350 g/m.sup.2, and a tensile strength between 500 lbf/in.sup.2 and 1800 lbf/in.sup.2.