... refractoriness. 3. Physicochemical stability. 4. High quality refractory raw materials. Calcined kaolin clay Characteristics: 1. High refractoriness. 2. Physicochemical stability. 3. ... ,3-5mm,5-8mm,8-15mmSand:16-30mesh,30-60mesh,60-80mesh,80-120meshPowder: 200mesh,250mesh,325meshPhysical and chemical indicators: ... 5249-5250-5350-5350-5350-5350-5450-55Fe2O3 % (max)1.01.151.31.52.02.53.03.5Ti02 % (max)0. ...