Gold

Gold has always been a sign of the wealthy because of its rare qualities. There is a very limited amount of gold worldwide, and many people will wear gold in jewelry where others can see it as a sign of their wealth. Gold has a very high density, so it is a very heavy metal. Because of its rarity, gold is often used by investors as a store of wealth and in the past various currencies have been backed by gold.

Properties

Gold is one of the most malleable and dense metals of all. It is very easy to shape, and is very heavy. Gold is one of the coinage metals, meaning that coins are frequently made out of or at least partially out of gold. Gold has a very shiny surface, which makes it not only rare, but also very beautiful to look at. It is a trivalent and univalent transition metal. Although gold does not react with surrounding chemicals, it is often attacked by chlorine, fluorine, aqua regia and cyanide. Mercury will eat away at gold, and will form an amalgam alloy. Nitric acid is commonly no soluble for gold, which is unique, because it will dissolve most any other metal. Because of the ability for gold to withstand the nitric acid, it will commonly be submersed in the acid to determine the value of the sample. This is where the phrase Acid test" came into use.[1]

History

All throughout history, all the way back into the prehistoric times, gold has been a metal of high value because of its beauty. It was one of the first metals used by humans for ornaments and rituals. Many times, Egyptian hieroglyphs often were portrayed with gold, to show the wealth of certain individuals of great importance. In the Bible, it was given as a gift to Jesus by one of the magi. Because of its easy malleableness, gold’s purity was often discovered by the one in possession of it, biting it. The more pure the gold, the easier it would be to score the metal.[2]

Uses

The single biggest use for gold is obviously in money exchange. It is used to weigh out the value of a dollar bill, without which, the paper would have no value. In many countries, gold is often used in expensive pieces of jewelry. In medieval times, coins were quite often used as a form of medicine. It was in their beliefs that something of such rarity and beauty could not be anything but good for your health. Gold is used in the making of computers as well. Because gold is a good conductor of electricity, it will often be used in motherboards for computers to transport the signals. Gold is used sometimes in photography, because it can be used as a toner that will shift the color of silver bromide lack and white prints closer toward brown or blue tones. There is a form of gold called white gold, which is used as a substitute for plutonium. all that white gold is, is a form of gold that has been mixed with platinum, palladium, nickel, or zinc; but regardless of its rarity, the beauty of gold is what makes it such a popular metal for so many uses.[3]

Rapid Formation

Geologists have shown that volcanoes can form gold quickly. One intesting paper on this subject was written by Simmons and Brown. Here is it's abstract.

"The Ladolam hydrothermal system, on Lihir Island, Papua New Guinea, hosts one of the youngest and largest gold deposits in the world. Several deep (more than 1 kilometer) geothermal wells were drilled beneath the ore bodies to extract water at >275°C and to facilitate open-pit mining. Using a titanium down-hole sampler, we determined that the deep geothermal brine of magmatic origin contains 15 parts per billion gold. At the current gold flux of 24 kilograms per year, this deposit could have formed within 55,000 years. The combination of sustained metal flux and efficient metal precipitation led to the formation of a giant hydrothermal gold deposit in a short period." ( Simmons and Brown; 2006)