Related Clues:

• It's refined
• Mineral deposit
• Refinery rocks
• Prospector's discovery
• Forty-niner's find
• I-5 state
• Tram cargo, perhaps
• Extraction candidate
• Underground-railroad cargo
• Mine content
• Eugene's state: Abbr.
• It may have a lead part
• Magnesium source
• Miner's discovery, perhaps
• It needs refining