Related Clues:

• It may have a silver lining?
• Pyromorphite, e.g.
• Mine car contents
• Valuable rock
• Rock with potential
• What some seams are made of
• Weak and ineffectual
• It may pan out
• Miner's bonanza
• Galena or mispickel
• Hematite, e.g.
• German preposition
• Vein contents, perhaps
• Bauxite or galena
• Iron, for one