Related Clues:

• Cargo on the ill-fated Edmund Fitzgerald
• Mined rock
• Substance for smelting
• Something to pump
• Copper source
• It's rough stuff
• Seam find
• Vein makeup
• Refinery metal
• Valuable vein
• Word with hand or fist
• Raw metal
• Waffle maker
• Contents of a lode-bearing wall?
• Source of gold