Had a Fun Tour of a Copper Mine Yesteday

Yesterday, my family and I, excluding my dad since he was at work, went on a tour of a large copper mine. The first thing we did is wait for a tour bus to arrive, since we missed the first one while getting gas. While we waited, we looked around the gift shop and found that they had a lot of copper-based goodies. When the bus arrived, we got on as soon as we could, hoping to see the mine. The bus left shortly after everyone was aboard. The guide told everyone about a herd of wild horses that roams the area, though they never showed up. This was understandable, seeing as they have hundreds of acres to run around in. As we passed the mine, our tour guide explained the basic process of mining, but he did not go into specifics yet, that was to come later. When we reached the top of the mine, we were looking over an immense, tiered, pit that was several miles across in either direction and very deep. That day it was quite windy, so we did not stay very long (don't worry, there was a high fence). While we were there, we saw several of the mine's 320-ton dump trucks and the machines they use to scoop up large piles of dirt to load into the dump trucks. The scoops required huge amounts of power, but did not have any engines, instead, they were connected to the mine's power grid by miles of 4-5 inch thick power cable. When we got back into the bus and drove back down to the main building, we actually got to go inside and see the inner workings of the refinery. First was the SAG mill, which takes rocks that are 8 inches or smaller and breaks them up into rocks that are 5 inches or smaller. Then the rocks are sent to the ball mill, where 8 pound and 18 pound steel balls grind them into powder. Then they are sent to a tank the combines the powder with water, pine oil, and a few other chemicals and then the mix is agitated. The chemicals and pine oil cause the copper to attach to the bubbles in the water, which then rise to the surface. the copper-coated bubbles are then skimmed off and all the added materials are separated. The resulting copped is called copper concentrate, and is about 28% pure copper. This is later melted down and formed in anodes which are then transported to a different location for smelting, after which the copper is about 99% pure and usable. The whole trip was quite enjoyable.