Some typical specifications of Indian refractories commonly used in the furnaces and kilns in steel, cement, non-ferrous metals and glass industries are given blow. These are illustrative and do not cover the full range of products and some of the improved items which have been recently developed.

HIGH ALUMINA BRICKS
CHEMICAL PROPERTIES
Al 2 O3 (%)	98.4 - 99.0	85 - 88
SiO 2 (%)	0.5 - 0.7	8.0 - 10.0
Fe 2 O3 (%)	0.05 - 0.07	1.0
PHYSICAL PROPERTIES
Hot Face Temperature (°C) (Max)	1870	1650
Bulk Density (gm/cc)	2.8 - 3.0	2.6 - 2.85
Apparent porosity (%)	18 - 23	17 - 22
Cold Crushing Strength (kg/cm²)	550 - 650	700 - 900
Modulus of Rupture (kg/cm²) at room temp.	180 - 200	150 - 175
Reheat change (%) (Max) at 1450&°C for 6 hrs.	±0.1	±0.3
Thermal conductivity (w/m°K) at 1000°C Hot Face temp.	3.0	4.1
Spalling Resistance	Fair	Good

BAUXITE BASED HIGH ALUMINA BRICKS
CHEMICAL PROPERTIES
Al 2 O3 (%) (Min)	70	80
Fe 2 O3 (%) (Max)	3.0 - 3.5	3
PHYSICAL PROPERTIES
Pyrometric Cone Equivalent (Orton) (Min)	36	37 - 38
Apparent porosity (%) (Max)	23	23
Bulk Density (gm/cc) (Min)	2.6	2.7
Cold Crushing Strength (kg/cm²) (Min)	400	400 - 500
PLCAR (%) (Max) at 1600°C for 2 hrs.	+3	+1.5
Remarks	High Alumina bricks resistant to alkali and slag attack, suitable for burning zone of Cement rotary klin ladle lining and EAF