Gold has always been the pearl of great price. Ever since gold was first mined in Kolar Gold Field of Karnataka state in India, the desire to see and use more of it has seized the hearts of men. Although gold enjoys a lot of patronage in the making of jewels, it has weaved itself even into technological gadgets like phones.

Before technology came to maturity, gold mining used to be instrumented with hoes and other tools with the ability to till the earth, which may be closely followed by the Panning process. This was mainly because the rush was not yet, so gold deposits were not far-fetched. But the process of gold mining has become a more complex one these days as the need and value of it is always on the increase.

Modern gold mining begins with prospecting by Geologists. The use of geological maps come handy, and geologist must have to study the chemical and physical properties of rocks to determine the presence and quantity of gold. Once that is Okayed around a particular area, there must be need to employ the expertise of geochemists, and geophysicists; coupled with airborne and remote sensing to enable drill testing of a sample.

The purpose of drilling is to take rock samples to examine for the presence, quantity, size, and quality of gold around the area. At this point, mining engineers are called upon to ascertain the type of mining to be employed, the physical obstructions to surmount before getting to the gold; and the environmental implications of erecting a mine in the area. The kind of mine depends on the depth at which the gold deposit is buried. If it is close to the surface, the miners will make an open-pit mine, but if deep down, they will have to make an underground mine.

Samples of the ore are taken to a metallurgist who goes through it to determine the processing method that would be used. For example, if the ore is a low graded one, the process will just involve the application of cyanide to help dissolve the gold before it is collected. But if the ore is of a high grade, it will be sent to a grinding mill for more extensive processing. On the other hand, if the ore was a Sulphide ore, it is allowed to oxidize in a sterilizer or autoclave to remove the sulphide, but a refractory ore is roasted at a high temperature to allow for smooth burning of the carbon and sulphide, after which it is taken to a leaching circuit.

When in the leaching circuit, gold extraction from the solution takes place, and is then chemically stripped by applying it on activated carbon. Since the gold gotten at this stage does contain up to 10% of impurities, they are transported to a refinery for further processing after being melted into a special kind of bar.

At the refinery, the impurities are converted into metallic chlorides so they can easily wash off of gold. The remaining deposit is now 99.5% pure gold, which is then put into electrolytic cells after being cast into anodes. By the application of electrolysis on the gold electrode, further purification takes place leaving the final result to be gold deposit of up to 99.99% purity.

After all this is done over the years around a particular area, the reclamation process must follow so as to give back to the land.

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