Abstract: A dental porcelain composition comprising a continuous glassy phase and a discontinuous, substantially uniform crystalline phase comprising cubic leucite. The porcelain exhibits coefficients of thermal expansion in the range of about 11 to about 17.times.10.sup.-6 /.degree. C. (measured from 25.degree. C. to 500.degree. C.) and fusion temperatures in the range of about 700.degree. C. to about 1200.degree. C. The porcelain composition of the present invention can be used to form dental restorations such as cores for all ceramic restorations. The cubic leucite phase is uniformly dispersed in the glass matrix and has an average grain size not exceeding about 4 .mu.m and about 95% of the leucite grains do not exceed about 8 .mu.m in diameter.