Related Clues:

• ''Giant'' discovery
• Rock that's mined
• Metalliferous rock
• Use 3-IN-ONE, e.g.
• What the Ewings and Clampetts had in common
• Assayer's raw material
• 2-Down, for one
• Museum piece, maybe
• Prospector's quest
• Viscous liquid
• Water's antithesis
• Kind of filter
• __ field
• Profitable rock
• Part of EVOO