The production of a new abrasive carbide of boron is briefly outlined. The manufacturing process is similar to that for silicon carbide. The losses of boron are negligible, and on this the commercial practicability of process for the new boron carbide is based. Completely dehydrated commercial boric acid is used as raw material, together with high purity coke. The reaction temperature is 2,500°–2,600° C. During the furnace operation the innermost zone melts, forming the carbide. Crystalline B4C has a very low vapor pressure at high temperatures and does not distill. The intrinsic hardness of B4C exceeds that of SiC. Molded B4C gave an average modulus of rupture in compression of 18,000 kg./cm.2. In cross bending, the modulus of rupture is less than that of cemented tungsten carbide. The resistivity at 20° C. is 0.445 ohms/cm.3. The coefficient of expansion between 25° to 800° C. is 4.5 × 10−6. The carbide is inert in all solutions of acids and alkalies, both concentrated and dilute. Industrially, B4C is used for drilling cemented tungsten carbide die nibs, nozzles for abrasive blasting, jeweled bearings in place of sapphire, wire drawing dies, etc.