Gold
Gold is one of the rarest precious metals found on Earth and has been used to symbolize wealth, riches, status for centuries. Today, gold is still as popular as ever, being used mainly in jewelry, but also various other industries where its unique properties are put to use.
For centuries gold has been used as a standard of monetary exchange and has been used to back the currency of countries, as specified in the gold standard. Many gold bullion coins are still in circulation, most of which are collected by investors or collectors and usually contain about 22 Karats or 24 Karats of gold. From 1526 to the mid-1930s, gold bullion was made of a 22 Karat gold alloy called crown gold, which was used for hardness. Naturally occurring pure gold is the softest of all metals and therefore is usually hardened with various other metals, mostly copper, as a means of hardening the gold. Today most gold coins are produced with 24 Karat gold, although there are various coins still produced with 22 Karat gold based on historic tradition, some of which include the American Gold Eagle and the British Gold Sovereign. The purest of all bullion coins is the Canadian Gold Maple Leaf which contains 99.999 percent pure gold. There are also various other pure bullion coins such as the Australian Gold Kangaroos which are rated at 99.99 percent pure, as well as the Australian Gold Nugget, Australian Lunar Calendar series coin, and the Austrian Philharmonic coin. Currently, the United States Mint produces the American Buffalo coin, which also has a purity of 99.99 percent. Today, most countries no longer produce gold bullion coins as the price is impractical, so gold coins are no longer used in circulation, but are still collected by collectors and investor alike.
Gold is also used as a major component of many electronic circuit boards and components. Because the concentration of free electrons in gold metal is 5.90×1022 cm-3, it is highly conductive to electricity, and has been used for electrical wiring in some high energy applications. Though silver is even more conductive per volume, gold has the advantage of being corrosion resistance. During the experimentation of the Manhattan Project’s atomic elements, gold wires were used.
Gold is also used on connectors of many electronic components, such as USB connectors, audio and video cables, circuit board connections, PCI and RAM cards, CPU processor connection to the motherboard, as well as many others. The good conductivity of gold, as well as its resistance to corrosion or oxidation make it ideal for creating good connections. In most cases the connector is primarily made of tin and is then coated with a thin layer of gold to ensure a perfect connection. However it is debated over whether or not gold is needed in these connectors and it is called unnecessary by most critics, saying consumers do not need gold plated connections and that it is only a marketing scheme. Gold is necessary in humid or corrosive environments, as well as environments where a connection failure could have devastating affects, such as in communication equipment, spacecrafts, jetfighters, aircraft engines, and supercomputers.
The recycling of circuit boards and other computer components is common practice as many contain gold connectors. There are a number of methods that may be used, including reverse electroplating, which is the easiest and the most popular way. However, depending on the type of components you obtain gold leads from, it may yield anywhere between only a hundred dollars or so to thousands of dollars worth of gold. High quality RAM and CPU units contain a high content of gold leads and by far yield the most gold.
