How to Cast Gold Bars

Large Gold Bars

• 1

  Use a large crucible to melt the gold in a refining furnace. The crucible can contain as little as 450 ounces of gold or as much as 30,000 ounces. Tilt the crucible to pour a small amount of gold into a pre-heated transfer crucible. Pour the melted gold from the transfer crucible through a gas flame into a pre-heated, cast-iron mold of 100 to 400 ounces. Position the gold on a balance to record the weight. Stop pouring at the required weight.

• 2

  Tilt the mold and drop the bar into a tank of water for cooling within seconds of the pouring. This procedure is called "quenching." Clean the bar with a soft cloth to remove stains. Weigh the bar. Mark it with a serial number or official stamp. Use a template stencil to manually mark the bars or place the bars into a press, which will mark some or all bars simultaneously.

• 3

  Produce small gold bars by using refined gold from gold granules or small pieces of gold. Place the gold on the balance and weigh it precisely. The amount of gold should weigh more than the bar weight to allow for loss during the manufacturing process.

• 4

  Place the gold in a crucible. Place the crucible in an induction or resistance-element furnace with temperatures around 1,200 degrees Celsius. Pour the melted gold into a pre-heated, cast-iron bar mold. Direct a soft gas flame into the mold to ensure that the top of the top surface is the last to solidify. This will make the top of the gold bar smooth. Tilt the mold and drop the bar into a water tank to cool.

• 5

  Make long, flat, gold bars by clasping several molds together vertically. Pour the melted gold into the open end of each mold. Unclasp the bars and remove the gold when it has solidified.