74109805
Oct 25, 1990
Oct 20, 1992
refractory building materials; namely, mixes, linings for furnaces, mortar, bricks, concrete, cement and prefabricated refractory elements of mineral materials; namely, prefabricated refractory blocks and prefabricated shapes used for industrial furnaces and parts thereof, including furnace roofs, electric arc furnaces, ladle furnaces, ladle bottoms and rolling mill furnaces
Nonmetallic Building Materials