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How is gold taken out of the ground?
Question Date: 2013-06-06
Answer 1:

Gold (Au) is mined. Most gold deposits are hydrothermal. This means that solutions deep in the crust move from depth towards the surface. These fluids are not pure water but have dissolved ions such as Au ions. These atoms of Gold are carried in solution mainly as chloride complexes AuCl (aqueous). When the solutions ascend they cool down and flakes of gold are precipitated from solution. Geologists find these hydrothermal gold deposits and then excavate the rocks, crush them and separate the gold flakes from the waste.

Another source of gold is called a PLACER deposit. These are sedimentary deposits in which gold flakes and nuggets are concentrated by fluvial processes (i.e. streams transport of bed load). Eventually the heavy minerals like native gold end up concentrated in the gravel deposits.

Answer 2:

Gold is mined.

Gold is one of the few metals that can be found as actual gold and not as gold ore (ore is minerals containing the metal that need to be smelted). Unfortunately, the process of extracting gold ore is really bad for the environment, because it uses mercury, which is very poisonous.

Answer 3:

Taking gold out of the ground is called, "mining". There are two main types of mining: placer and vein. Placer mining is when the gold is found with other products of dirt and sand and then is separated out. Usually this is done with a pan and water where the sand and dirt float to the top of the bottom and the gold stays at the bottom. Vein mining is the most important where gold is obtained from processing thousands of ounces of ore. The method is more extensive and requires a lot of refining. Gold was discovered right here in a Northern California river in 1848 by James Marshall; this is when the gold rush started. If you go to Sacramento, California, there are places where you can go mine for gold yourself, and you get to keep the gold you find!

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