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How to Get Gold Out of Solid Rock

The average concentration of gold in the Earth's crust is 0.005 parts per million. For mining to become viable, ore needs to be approximately 1,000 times more concentrated, according to the Bullion Vault website. Gold may be concentrated over thousands of years after being dissolved out of bedrock and carried to a point where it regains its solid form. Once a vein of gold is discovered, it must be extracted from the surrounding rock.

Things You'll Need

Gold ore
Hammer
Chisel
Pestle
Mortar
Sheet of No. 18 mesh
Prospecting pan

Instructions

- 1
  Chisel the large rocks into more manageable chunks no larger than a fist.
- 2
  Put a chunk of rock into the mortar and crush it with the pestle until it will fit through the mesh. (The mesh scale relates to the size of the openings that granular material may pass through. In a No. 18 mesh, the openings measure 1 mm or 0.0394 inches.) Remove any rock and gold that is quickly crushed. This will make it easier to crush the remaining larger pieces to the desired size.
- 3
  Sieve the crushed material through the mesh into the pan. Move the pan in a gentle circular motion. Lighter rock and other unwanted material will move to the outside of the pan, leaving the heavier gold nearer the center.

Rocks & Minerals