The distance the zinc concentrate travels from mine to smelter is relatively small. Once the zinc is concentrated at the mine it is transported to the smelter. This process is repeated multiple times until the resulting froth is thick and containing 62-65% zinc concentrate (Nyrstar Tennessee Mines). The zinc sulfide froth overfills from the top of this cell into the next cell. The zinc sulfides, now hydrophobic, attach to the bubbles and rise to the surface of the slurry to the top to create froth. Frothing agents such as MIBC and DSF specialty range are added to the slurry and air is then released from the bottom of the cell. These chemicals attach to the zinc sulfides to make them hydrophobic, or to have little or no affinity for water (). The collector chemicals are a very small portion of the mixture. Each cell is filled with water, ground ore, and collector chemicals such as xamthates, dithiophosphates, and/ or thionocarbamates (Orcia). The froth flotation is divided up into cells, which usually cascade onto each other to further concentrate the zinc. The froth flotation process separates the zinc sulfide from the rest of the ore. Once the ore has been reduced to a fine powder they are put through a froth flotation process. The concentration process begins by crushing and grinding the boulders and rocks until they are almost a fine power (International Precious Metals Institute). The boulders and rocks that are drilled, blasted, and scaled from the walls are then sent through a concentration process which occurs onsite of each of these mines. (International Precious Metals Institute). Despite the high energy needed to extract the mineral from the surrounding rock, the value of the mineral is very profitable. The mineral content in the rock from these mines only contain 3-11% of zinc (Metallurgical Industry). “Scalers”, large underground vehicles, are also used to knockdown loose rock from mine walls (Knoxville News Sentinel). These zinc mines are underground drill and blast mines. one cent coin comes from the Tennessee Valley Mines this mine group is comprised of 6 mines: Young, Immel, Coy, Elmwood, Gordonsville, and Cumberland (Smelting and Alloying). Extraction and concentration requires great energy and processing to acquire the valuable metal. Zinc is the fourth most important metal in the world, as far as quantity produced following iron, aluminum, and copper (Sibley). Zinc is most commonly derived from sphalerite which is a zinc sulfide. Neither zinc nor copper occur as pure minerals in nature. The two main raw materials in the current US one cent coin are zinc at 97.5% and copper at 2.5%. The costs of the raw materials are too great to keep the U.S. This is directly related to the materials cost (CC Enterprises LLC). one cent coin is 1.83 cents but the value is still only 1 cent. The penny is often discarded in our society, the leave a penny tray is a great example. In today’s modern world the penny has no relevance and is too expensive to manufacture. one cent coin has had a wonderful history and many composition changes since its creation in 1787. Today our pennies consist of 97.5% zinc and 2.5% copper and cost 1.83 cents to create. In 1982 the composition changed yet again the penny became primarily zinc with a thin copper plating (McMorrow-Hernandez). In 1943 the copper was completely removed and replaced with steel do to World War II copper was reintroduced back into the penny in 1944. The one cent coin went through another composition change after the Civil War in 1864 to 95% copper and 5% zinc (A Brief History of the U.S. This penny consisted of 88% copper and 12% nickel (Cents). The price of copper was rising in the 1850’s and a smaller cent was developed. 1815 was the only year no one cent coins were minted due to a copper shortage caused by the War of 1812 (A Brief History of the U.S. Cent). The coin was much larger than the current penny, almost the size of the half dollar, and heavy the weight of the coin was directly related to the value of the copper it consisted of (Cents). one cent coin (A Brief History of the U.S. This coin, known as the Fugio cent, was made of 100% copper and designed by Benjamin Franklin in 1787(McMorrow-Hernandez). The penny is the first coin minted in the United States (A Brief History of the U.S.
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