Related Clues:

• The Columbia R. forms much of its northern border
• Word after iron or potash
• Sudbury Basin export
• One might take the lead from this
• Pacific st
• Heavy metal rock?
• Mispickel or cinnabar, e.g
• Train cargo, perhaps
• Mispickel or cinnabar
• Galena, e.g
• Metallurgist's subject
• Its processing produces slag
• Miner's haul
• The gold in them thar hills, say
• Hematite or limonite