PREPARED PULVERIZED MATERIAL CONTAINING CARBON, KNOWN COMMERCIALLY AS HOT TOPPING COMPOUND; OR AS FOUNDRY FACING; TO BE APPLIED TO MOLTEN METAL SURFACES OF INGOT HEADS OR CASTING RISERS, FOR PROVIDING THEREON A FLUFFY HEAT-IN-SULATED BLANKET-LIKE COVERING, THAT LOCALIZES THE SHRINKAGE ON SAID HEADS OR RISERS AND PREVENTS FORMATION OF DEEP WASTEFUL CRACKS OR CAVITIES