Al2O3 : 78-80 % Water Absorption: 4.5-5.5 % Bending Resistance: £¾72 Mpa Density : 2.8-2.9 g/cm3 Thermal Shock Resistance: very good Thermal Expansion: 5.5 10-6xK-1 (20-1000 0C) Maximum Working Temperature: 1400 0C Refractoriness: 1850 0C. Wooden box.