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How to Extract Gold from Mines

Modern gold mining has advanced far from the days of the pick and the mule. Many mining districts are being revived with corporations investing in specialized heavy equipment and processing plants on site to reach deeper and extract gold more efficiently at mine sites. Many processes, like drilling blast holes and using chemical reactions to process the ore, are time honored but newly refined; miners use satellite technology to locate blast sites and unmanned, remotely controlled drilling equipment to venture into less stable areas without taking the risks early prospectors and miners faced every day when gold mining was a manned, underground activity.

Instructions

- 1
  Locate any previous workings. Mining areas are often historical zones, with various means of extraction having been used over the course of decades. New mining techniques are able to extract and process ore unreachable or not extractable before, but you must locate unstable earth from past digging and follow safety procedures to avoid working manned machinery over shaky ground.
- 2
  Drill blast holes. The depth of the holes and location will depend upon the specific geography of your mine; drill holes 20 or more feet deep and set in a pattern or grid.
- 3
  Charge the holes with explosives and detonators; then "plug" them with a specifically formulated gravel mix to direct the blast into the rock and not out the top of the hole. Notify the public if appropriate and clear the mining area. Detonate the explosives in a sequence designed to crush the rock without creating vibrations in excess of licensing limitations. Mining corporations must limit sound, vibration and geological and ecological disturbances to maintain a good relationship with the larger community and with environmental regulatory agencies.
- 4
  Identify and remove any undetonated explosives and "mark up" the broken rock (called "muck"), flagging material containing ore and locating and marking the "overburden", rock that does not contain ore. Design a plan for extracting the usable muck. Dig the muck with shovels and load into trucks; tag each truckload for a destination based on its load. Muck may be taken to storage, a backfill area or the crusher.
- 5
  Clear, clean of debris and grade the mined area to maintain safety and as a precursor for later reclamation. Mined land can be reclaimed and replanted and local wildlife can be encouraged once the ore is removed. This process is difficult and can take many years.
- 6
  Crush and grind the ore-containing muck. Crushing rock is largely an industrialized version of the old grinding stones powered by mule or men in prospecting days. Weights are used to swing and crush, and balls (steel today rather than stone) are used with water to grind. The process today uses a great deal of electrical power. The process crushes the rock into softball-sized pieces and then grinds it finely with water to create a "slurry."
- 7
  Process the slurry using chemical reactions to pull the gold from the ore and then to release it again. Use cyanide and carbon in leach ponds or tanks. Collect the accumulated gold and heat it to melt and form bars for transport to a refinery where the silver can be removed and nearly pure gold made ready for use.

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