Gold is purified by means of a smelting process, which utilizes pressure, high heat and chemicals to accomplish the task. Like any metal that appears naturally in the earth, there are impurities that must be removed. Removing minerals and other impurities allows gold to be used in its purest form, which is necessary in many applications, particularly in jewelry and electronics. Gold is utilized frequently for electronic applications because it does not tarnish or rust over time.
The first step in the gold smelting process occurs when ore containing gold is mined from the earth. At this point, the crude binding matter and the gold metal need to be separated. This is accomplished by pulverizing or crushing the gold ore, and then placing it in a furnace. The furnace must reach temperatures in excess of 1064 degrees Celsius, in order to elevate the gold above its melting point.
While many impurities are burned off in the furnace, other metals remain. Gold ore extracted from mines in the earth contains a significant amount of impurities, including traces of other metals. In order to separate the gold from other metals, chemicals such as cyanide solution or mercury are introduced to the gold. This process causes the gold to coagulate, and form nuggets and clumps of gold.
Use of Purified Gold
After the gold smelting process is complete, the gold is melted once more, and poured into molds to form ingots. Later, the gold ingots may be used for various purposes fulfilled best by this precious metal. Some of this gold is used for jewelry or electronics contacts and may later be recycled for other uses. In the event that gold from jewelry or electronics is to be recycled, the scrap gold must go through another smelting process in order to be considered pure once more.