New lightweight, high-strength porcelain bodies, using only nonplastic raw materials such as glass microspheres, quartz, and alumina cement, were fabricated and the effect of quartz particle size was investigated. Decreases in the green strength, relative to an increasing content of glass microspheres, were attributed to the decrease in the density and the relative decrease in the volume of alumina cement. The phases in the fired body mere glass, alpha-quartz, cristobalite, anorthite, and a small amount of alpha-alumina. The large quartz particles (10-32 mu m in size) could not be densified to closed porosity, because of underfiring, whereas smaller quartz particles (4-10 mu m in size) permitted densification to closed porosity at 1300 degrees C. The high flexural strength when using medium-sized quartz particles (6-20 mu m, content of 30 wt%) was attributed to a stronger prestress and higher density that was due to better vitrification.