How to Refine Black Sand

Remove the majority of black sand from your sluice box or rocker cradle with a spatula and place it into a large bucket. If using a sluice box, remove the runners and empty the carpet contents into the bucket. If you have panned concentrate, pour it straight into the bucket.

Place a screen which has 1/4 or 1/2-inch mesh on another bucket and scoop the contents from your container bucket over the screen. Pile two or three scoops on the screen and feather the surface with a spatula, or by hand, shoving the larger particles through the mesh. Remove and discard any large rocks or stones.

Remove the large coarse mesh screen and place an 8-mesh screen over the other empty bucket. Load three scoops at a time, pushing the smaller concentrate sand through the screen, and discard the larger stones and pebbles left behind. When you reach the bottom of the container bucket, use some water to empty the remaining concentrate into the screen.

Swap the 8-mesh screen for a 12-mesh screen. Perform the same sifting procedure, running all of the concentrate through the screen. Use a magnifying glass and tweezers to pull out any suspect grains that appear to be small gold nuggets or large gold flakes. Place the gold on a flat piece of white paper, and fold it over, to keep the contents inside.

Trade the 12-mesh screen for a fine 20-mesh screen. Perform the same operation of sifting the concentrate in batches, and examining the concentrate for fine gold nuggets or flakes, with the magnifying glass. Look for any gold that might adhere to fine black pebbles and transfer them to your paper receptacle.

Examine the concentrate you have accumulated through the sifting stages. The amount of concentrate should be greatly reduced. Place the concentrate in a steal gold mining pan and heat the bottom with a small propane torch. Use the spatula to mix the concentrate, allowing it to completely dry. Excess heat will bubble and splatter gold out of the pan, so keep the temperature regulated for drying only.

Pour the black sand concentrate onto a flat piece of paper. Make sure you do this inside a wind-free structure. Use the magnifying glass and artist brush to delicately separate any gold flakes from the sand, and transfer them to your paper receptacle. Spread out the sand over the paper and lightly blow over it -- this will cause the light-weight black sand to drift off the paper.

Run a magnet over the rest of the concentrate, to remove any fine iron particles. Use the brush and tweezers to remove any remaining visible gold particles. Fold your receptacle paper and pour the gold contents into a collecting bottle, via a small funnel. Pour the remaining black sand, if you have any, into another collecting bottle, via a funnel. Keep the remaining black sand, if you decide to further break it down with a chemical process to remove any remaining microscopic gold.