Related Clues:

• It may have a silver lining?
• Igneous rock, once
• Pyromorphite, e.g.
• Mine car contents
• Valuable rock
• Soft rock?
• Rock with potential
• What some seams are made of
• Volcanic outflow
• It may pan out
• Miner's bonanza
• Mantle piece?
• Galena or mispickel
• Hematite, e.g.
• German preposition