Related Clues:

• Smelting dross
• Smelter stuff
• Metal waste
• Mill by-product
• Volcanic output
• Refuse in a foundry
• Coal waste
• Steel mill refuse
• Cinder
• Smelting leftovers
• Refuse to get rid of
• Steel mill by-product
• Refinery dross
• Refinery waste
• Remains at a steel mill