Abstract: The burner block or tile in industrial furnaces is conventionally made of refractory ceramic material. Such refractories are susceptible to cracking from thermal shock if the temperature of the burner block fluctuates during use. The life of the burner block can be greatly improved by making it in two parts: a cavity bounding inner part made from a material more shock resistant than a conventional refractory and a conventional refractory outer part. Best results are obtained with a thin inner liner of recrystallized silicon carbide having a thermal conductivity of over 18 W/(m K) and a modulus of rupture of at least 120 MPa.