for each ton of ore treated, there would be 3576. POQ~d8. of slag formed) • Tae. metallic values in this. slag run too low to be saved economically. in. practice; and, therefore, are allowed to. go to waste. In the suooeeding design of a smelting plant to treat this ore, this slag is to be granulated. and sold to railroads for ballast. TREA ...