How Jewelry Is Made
The “Lost Wax” Method
Casting gold and silver to make jewelry is nothing new. It has been done for eons. Evidence has been found dating the process back over 2,000 years. Although, time has brought about refinements in materials and technique, the basic method is unchanged.
We have to have a “model” of the desired item. The “model”, made of wax, can be hand carved or printed by utilizing a CadCam computer. The wax is then mounted in a steel tube into which plaster is poured. The tube or “flask” is placed into a vacuum chamber removing bubbles in the plaster that might ruin the casting later.
Then the flask is put into a special oven and heated overnight at about 1,800 degrees. This process burns off the wax model (Lost Wax method) leaving a void in the plaster. The hot flask is then placed into a casting machine where molten gold, silver or platinum is poured into the mold while spinning at high speed.
This forces the metal into the void left by the burned out wax. After a few minutes, the still hot flask is placed in cold water making the plaster boil off and leaving just the newly cast metal object. The work done to this point represents approximately half of the labor needed to produce a piece of fine jewelry.
The new jewelry is cut away from extra metal needed for casting. This metal is recycled for future use. The new jewelry item is usually a bit rough and requires much sanding and polishing to reach the desired appearance. The jeweler will then set the stones into the metal and do the final grinding and polishing to finish the item.