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How to Build a Gold Concentrator

Gold is a rare and beautiful metal. It tends not to react with the other elements, and so it is often found in pure form in nature, usually as tiny flakes or nuggets. What's more, it's remarkably dense, and a simple flow of water can wash away most lighter minerals, leaving behind gold and a few other heavier substances such as hematite and magnetite which appear as a kind of black sand. Traditional panning for gold yields this mix of heavy minerals, but you can further separate out the gold with a simple homemade concentrator.

Things You'll Need

Large plastic funnel
Sharp mat knife or box cutter
Large plastic bowl (thin or flexible enough to cut)
Waterproof glue
Plastic garden hose
Duct tape

Instructions

- 1
  Cut the funnel at the point on the cone where it is approximately 1 to 1 1/2 inches in diameter. Try to make the cut as regular and flat as possible.
- 2
  Glue the wide end of the funnel to the bottom of the bowl, centered so that it resembles a pan for baking angel food cake. Ensure the seam between the funnel top and the bottom of the bowls is smooth and watertight.
- 3
  Cut a hole in the bottom of the plastic bowl, being careful not to damage the funnel or the seam with the bowl. When the concentrator is finished, water will swirl around the cone and then spill down through the hole in the cone, draining through the hole in the bottom of the bowl, so make it about the same size as the hole in the cone to accommodate the flow.
- 4
  Cut off the end of the garden hose to which you would normally attach the sprinkler or sprayer.
- 5
  Cut a horizontal slot in the side of the bowl, about half the height from the bottom as the top of the cone, and long enough and wide enough that you can thread the bare end of the hose through the slot at an angle almost tangent to the side of the bowl. Water will flow through this hose into and against the side of the bowl to create a strong circular flow around the bowl, so ensure the slot is wide enough to allow the hose to carry some current; it shouldn't be squeezed completely flat.
- 6
  Thread the hose into the slot, and adjust its position to direct a jet of water along the inside of the bowl. You may want to connect the other end of the hose to a spigot and turn it on to check. Once you are satisfied with the position of the hose, dry everything off and carefully secure the hose in place with waterproof glue, as well as duct tape on the outer surface of the bowl.
- 7
  Scoop a couple of cups of paydirt into the bowl, and slowly turn on the flow of water until you have a nice flow. Let it run until you see a star-like pattern forming in the black sand around the base of the cone. You may see tiny flecks of gold at the star's points, left behind as the water carries away the lighter minerals. If so, your gold concentrator is operational.

Rocks & Minerals