Related Clues:

• Pitchblende and bauxite
• Subjects of assays
• Unrefined metals
• Mining take
• Ones in need of refinement
• They may be driven to extraction
• Refinement targets
• Iron and copper, e.g.
• Miner samples
• Mine output
• Raw rocks
• Things tunnelers look for
• Tramcar contents
• Underground discoveries
• Contents of trams