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Gold Refining Instructions

Gold refining is a process most can accomplish using acid solutions. It gives the experienced hobbyist nearly pure gold from any scrap metal containing the smallest amount. The process involves several steps, as well as lots of heat, acid chemicals and toxic fumes. Great care and patience is required to properly refine gold using acid solutions. If you follow safety precautions, the practice yields a valuable investment for the future.

Things You'll Need

Gold metal
Heavy glass containers, pyrex
Nitric acid
Hydrochloric or muriatic acid
Urea
Gold precipitant
Aqua ammonia
Water, tap and distilled
Hot plate
Plastic stirrer
Coffee filter
Buchner funnel
Crucible
Torch

Instructions

- 1
  Place items containing gold in a Pyrex glass jar.
- 2
  Add nitric acid or a substitute to the container. Use 30 milliliters of nitric acid for every ounce of metal.
- 3
  Wait thirty minutes. Fumes may develop and the solution may turn brown. If you're using the nitric acid substitute you do not need to wait. Move to the next step.
- 4
  Add 120 milliliters of hydrochloric or muriatic acid for every ounce of metal to the nitric acid already in the container.
- 5
  Leave the pot overnight. Fumes and heat are likely to develop. By morning the acid solution should be a clear green color.
- 6
  Pour the acid solution, carefully, into another Pyrex container capable of taking heat. A Buchner funnel sufficiently filters out larger particles without melting.
  
  Do not pour out any metal particles with the acid. These particles are not gold and they will lessen the purity of the gold you refine.
- 7
  Boil 1 cup of water and mix in one pound urea.
- 8
  Slowly add the urea solution to the acid solution, which will begin to foam. Stop adding urea when the acid stops reacting to it. This neutralizes the nitric acid.
- 9
  Mix 1 quart of boiling water with 1 ounce of gold precipitant for every ounce of metal being refined. Some of the common precipitants are aluminum dust, Vitamin C, and zinc dust.
- 10
  Slowly add the precipitant to the acid solution. It will turn a muddy brown with small particles of pure gold. Let it rest for thirty minutes. You can then test the solution to ensure all the gold has precipitated out of the acid solution.
- 11
  Pour the acid solution into another container. Filter to catch loose gold. Keep as many of the particles in the first container as possible.
- 12
  Rinse the muddy particles several times with water. Pour water into the container with the gold and stir. Pour off the water, using the filter. Repeat four times.
- 13
  Rinse again with aqua ammonia. The ammonia cleans the gold of any remaining impurities and neutralize remaining acids.
- 14
  Rinse again with distilled water.
- 15
  Heat the gold-filled container on a hot burner to evaporate all liquid. The gold should be slightly brown, dry and look powdery.
- 16
  Heat the dried gold in a crucible until molten. Pour off to cool. When cool, pop it out of the mold.

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