... , petrochemical, ceramic, glass and carbon black industry. ItemFireclayHigh aluminaHigh alumina, light weightInsulating brick Mullite, low iron contentHollow ball, alumina0.81.30 ... (350±25), w/(m.k), ≥0.350.50.350.60.250.50.60.71.2(1000,hot side)Refractoriness,, ≥160015001750>1790