Copper
Category : Industrial Materials
Copper is a chemical element with symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color. It is used as a conductor of heat and electricity, as a building material and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins and constantan used in strain gauges and thermocouples for temperature measurement.
Centuries before it was identified as an element, zinc was used to make brass (an alloy of zinc and copper) and for medicinal purposes. Metallic zinc and zinc oxide were produced in India sometime between the 11th and 14th centuries and in China in the 17th century, although the discovery of pure metallic zinc is credited to the German chemist Andreas Marggraf, who isolated the element in 1746.
The lead, zinc and copper veins on Mendip were deposited by hot mineralising fluids (typically between 50 and 150° C) rising up from depth and depositing various minerals as they cooled. The source of the fluids were the deep sedimentary basins either side of the Mendips. As the Triassic and Jurassic sediments in these basins were buried, compacted and heated over time, some of the water in the rock was forced out, along with any dissolved metals and migrated into the neighbouring Carboniferous Limestone. Here the change in chemistry, temperature and pressure led to the deposition of various minerals including lead, zinc, and locally copper.