Gold - Part 1
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Gold. The very word stirs the imagination, conjuring pictures of vast treasures of shimmering yellow metal. Gold has started mass migrations, nearly emptying cities as men swarm the hills, desperately searching for the precious metal. Gold has launched conquering armies, sending Spanish conquistadors to crush entire civilizations to get more for the greater glory of Spain, not to mention their own pockets. Gold sent English privateers to the Caribbean to steal it while the Spanish fought to send it to Spain. For as long as history records, and even longer, mankind has gone to great lengths and great risks to find gold. The Ancient Egyptian Pharaohs discovered a particularly rich gold mine in a country called Nubia. The Egyptian armies took over the land and used the gold to manipulate rival empires. Gold has caused all this and more, but what is gold?
Gold is an element. Gold doesn’t react with very many other elements. It will not corrode or rust away. Most acids won’t even eat it away. In fact, one of the ways to test if you have real gold or fake gold is to dip it in acid and see if the acid eats it away.
Gold is shiny and people like the look of it. Gold is used for money and jewelry. Gold is a very soft metal; the softness of gold makes it easy to bend and shape but it doesn't hold its shape very well. This isn’t very useful if you want to make jewelry. The solution has been to add other harder metals to gold. So how do you add metal to another metal? The trick is, you have to melt the metals to liquid then mix them together. A combination of metals like this is called an alloy. People have been making alloys for a very long time. For example, bronze from the Bronze Age is an alloy of copper and tin. When gold is made into an alloy its purity (the amount of gold metal in the mix) is measured in karats. 24 karat gold is pure gold; the lower the number the more other metal has been added. The gold alloys used in modern jewelry are 10 karat or 14 karat gold. 10 karat gold has less gold in the alloy but is harder. 14 karat has more gold and is softer. White gold is an alloy created by adding metals that change gold's yellow color to silver. Like yellow gold, the most common alloys of white gold are 10 karat and 14 karat gold.