Mountain To Mint – How Bullion Is Made

Silver, Gold and other precious and non-precious metals have been mined from mountains since 3000 B.C. or earlier. Bullion is generally gold and silver refined into a bar or round coin.

Utah is home to one of the largest mining holes on earth. The Bingham Canyon Mine, more commonly known as Kennecott Copper Mine, is one of few man-made things visible from space. The pit is over .75 miles deep and spans over 3 square miles.

The mine was originally a rich source of copper, silver and gold with other minerals extracted from the same mine. During the Gold Rush, gold was dredged from river rock in California. Nevada is home to some of the largest gold mining operations in the United States. Gold makes up approximately 38% of the total precious metals mining of the $82 billion dollar industry in 2020.

Raw silver ore usually is found with trace amounts of other minerals. It is a chemical element with symbol Ag. Gold is also found on the periodic table as Au. Mining processes vary, but in commercial scale are usually done with heavy equipment where large swaths of earth are removed through blasting or digging in open pits or tunnel mines

While gold, silver and other precious metals can be found in large nuggets or chunks, it usually takes effort to separate the precious metals from other elements and each other.

Refining Precious Metals

The refining process, or separation and purification, uses one or more of several common methods including acid, fire, electricity and the Miller Process and Cupellation. The Miller Process, for example, involves melting the gold, passing chlorine gas through it to solidify impurities, and then further electrolytically purifying the gold.

During the Gold Rush, other methods were used in the sluicing process running raw materials through water over a corrugated or gate type surface. The heavier gold would stay in the sluice box while other debris would return to the river. One of the most environmentally harmful practices involves using liquid mercury to separate often tiny flakes of gold from other mined materials. It acts as a sort of gold magnet. Mercury is dangerously harmful to humans and nature but is still used today.

If ore contains silver and gold, it is often treated with sodium cyanide to dissolve the metals. Powdered zinc is added to form a sludge from which the gold and silver are further refined.

Refined gold and silver shot ready to be turned into bullion

Silver is mostly found in North America, Peru, Chile and Australia while India is the largest consumer of silver in the world. Silver is most commonly refined through Cupellation which involves blowing air bubbles through molten silver where the purified ore is skimmed off the top like a froth.

There are many processes, but none are commonly known. Likewise few outside the business know that refined gold and silver are usually transported in grain or shot form.

Minting Bullion

The minting process usually involves melting the refined metal into liquid and pouring into molds or casting for bars, or extruding it into billet or tubes for rounds or coins. The extruding process creates sheets or strips. It is then punched or cut into rounds.

The rounds are further stamped or struck with special die to create the appearance of a coin. Bars are often struck as well with a design, letters or a mint mark.

In some cases additional finishing is done including polishing and engraving for added luster and design.

Bullion then is the refined metal either in bulk or finished state. Bullion differs from coins as it is not legal tender.

If you are interested in investing in gold or silver bullion, contact US Silver and Gold today! We have some of the best prices around.

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