Related Clues:

• Pyrite, e.g.
• Galena and bauxite
• Tramcar cargo
• Pac. NW state
• Dig this
• Alcoa purchase
• Panners' finds
• Mine rocks
• Ida. neighbor
• Assayer's concern
• They may be found in prospectors' sectors
• Iron or gold source
• Underground wealth
• See 75-Across
• They need refinement