The Sun You Can Touch

? One of the oldest metals used as money, and decor
? The most malleable and ductile of the known metals
? One of the only two coloured metal elements, the other being copper
                                We are talking GOLD here!

MINING:

GOLDEN ELEMENTA Gold is a chemical element with the symbol Au (from the Latin Aurum) and atomic number 79. It is a Noble metal – resistant to corrosion or oxidation. It does not react with most metals, but readily forms alloys. It is a good conductor of heat and electricity. It can be beaten thin enough to become translucent, transmitting greenish blue light! Gold is so soft that earlier people used to bite it to test its authenticity because the purer the gold, the easier it is to mark it. GOLDEN HISTORY In the Neolithic period, gold was collected from streambeds. By 3500 BC, early Egyptians (the Sumerian culture of Mesopotamia) started using mined gold to craft jewellery, religious artifacts, and utensils. Now, about 65 per cent of processed gold is used in the arts industry, mainly to make jewellery, and 25 per cent in industrial applications. Twothirds of the mined gold comes from South Africa, which has the world’s largest gold deposit in Precambrian Witwatersrand Conglomerate.

Gold occurs as nuggets or grains in rocks in underground Lode and alluvial (or Placer) deposits.
? Lode deposits: gold is mixed with another mineral (like quartz) in veins that fill splits in surrounding rocks. It is extracted by drilling, blasting, or shovelling the surrounding rock.
? Placer deposits: contain pieces of gold ore that wash down streams from lode deposits, mixed with sand or gravel. Gold is usually extracted by Power shovelling, Dredging, or Hydraulic mining.

GRINDING:
The gold is separated from the ground ore by any of these:-
? Floatation: The ore is put in a solution of frothing agent (causes the water to foam), collecting agent (bonds with the gold, forming an oily film that sticks to air bubbles), and a mixture of organic chemicals (keeps the contaminants from bonding with the air bubbles). Air bubbles are blown in (aerated), and the gold floats, attached to the bubbles.
? Cyanidation: The ore is put in cyanide solution. Zinc is added. The chemical reaction precipitates (separates) the gold from its ore, which is then separated in filter press.
? Carbon-in-pulp: The ore is mixed with water to form a pulp. Cyanide is added, which dissolves the gold, and then carbon bonds with it. The carbon particles are removed, and are placed in a hot caustic (corrosive) carbon solution, which separates the gold from the carbon.
? Amalgamation: The ore is passed over mercury-covered plates to form a goldmercury amalgam (mixture). The amalgam is heated, and the mercury boils off as a gas leaving behind the gold.
? Smelting: The gold is heated with a chemical substance called Flux, which bonds with the contaminants and floats on top of the gold. The fluxcontaminant mixture (slag) is hauled away, leaving a gold precipitate.

And the gold is ready for the mold!