USGS studies of copper consumption show some interesting trends for the to time period. Copper consumption in emerging economies, such as China and India, rose considerably, whereas the consumption rate in the United States fell slightly. Until , the United States was the leading copper consumer and annually used about 16 percent of total world refined copper about 2.
In , the United States was overtaken by China as the world's leading user of refined copper. The booming economy in China contributed to a quadrupling of its annual refined copper consumption during the 12 years from to Graph by USGS.
The USGS assessed undiscovered copper in two deposit types that account for about 80 percent of the world's copper supply. Porphyry copper deposits account for about 60 percent of the world's copper. In porphyry copper deposits, copper ore minerals are disseminated in igneous intrusions. Sediment-hosted stratabound copper deposits, in which copper is concentrated in layers in sedimentary rocks, account for about 20 percent of the world's identified copper resources.
Globally, mines in these two deposit types produce about 12 million tons of copper per year. This study considered potential for exposed and concealed deposits within 1 kilometer of the surface for porphyry deposits and up to 2. For porphyry deposits, tracts were delineated; tracts contain 1 or more identified deposits.
Fifty tracts were delineated for sediment-hosted stratabound copper deposits; 27 contain 1 or more identified deposits. Results of the assessment are provided by deposit type for 11 regions see Copper Deposit Map on this page. The mean total undiscovered resource for porphyry deposits is 3, million tons, and the mean total undiscovered resource for sediment-hosted deposits is million tons, for a global total of 3, million tons of copper.
The ranges of resource estimates between the 90th and 10th percentiles reflect the geologic uncertainty in the assessment process. Copper Deposit Map: Distribution of known copper deposits in Red indicates copper associated with igneous intrusions porphyry copper deposits and blue indicates copper contained in sedimentary rocks sediment-hosted copper deposits.
Map by USGS. Enlarge Map. South America has the largest identified and undiscovered copper resources about 20 percent of the total undiscovered amount. The world's largest porphyry deposits are mined in this region. Chile and Peru are among the world's top copper-producing countries. Most of the undiscovered resources are in a belt that extends from Panama to southwestern Mexico.
The estimated undiscovered porphyry copper resources are approximately equal to the identified resources. The leading copper-producing states in the U. In the United States, undiscovered sediment-hosted stratabound copper deposits in Michigan , Montana, and Texas are estimated to contain about three times as much copper as has been identified. Two giant deposits are known, in Michigan and Montana. Northeast Asia is relatively underexplored, with modest identified porphyry copper resources and only one identified giant porphyry copper deposit.
However, the mean undiscovered resources are estimated to be quite large. This region has the largest ratio of undiscovered to identified resources in the study. North Central Asia has 35 porphyry copper deposits, including a supergiant deposit in Mongolia and a giant deposit in Kazakhstan. The tract area is estimated to contain about three times the amount of identified porphyry copper resource. This region also hosts three giant sediment-hosted stratabound copper deposits, in Kazakhstan and Russia.
Due to its much lower cost and greater abundance, Copper has traditionally been the standard material used for electricity transmission applications. However, weight considerations mean that a large proportion of overhead high voltage power lines now use Aluminium rather than Copper. By weight, the conductivity of Aluminium is around twice that of Copper. The Aluminium alloys used do have a low strength and need to be reinforced with a galvanised or Aluminium coated high tensile steel wire in each strand.
Although additions of other elements will improve properties like strength, there will be some loss in electrical conductivity. Most Copper alloys will develop a blue-green patina when exposed to the elements outdoors. Some Copper alloys will darken after prolonged exposure to the elements and take on a brown to black colour. Lacquer coatings can be used to protect the surface and retain the original alloy colour. An acrylic coating with benzotriazole as an additive will last several years under most outdoor, abrasion-free conditions.
The yield point for Copper alloys is not sharply defined. As a result it tends to be reported as either a 0. Most commonly the 0. Hardening by cold working means the material becomes less ductile, and yield strength approaches the tensile strength. Commonly employed processes such as brazing, welding and soldering can be used to join most Copper alloys.
Soldering is often used for electrical connections. High Lead content alloys are unsuitable for welding. Ductility can be restored by annealing. This can be done either by a specific annealing process or by incidental annealing through welding or brazing procedures.
Copper alloys can be specified according to temper levels. The temper is imparted by cold working and subsequent degrees of annealing. Copper can be recycled without any loss of quality. For more information, see the Copper Recycling and Sustainability resource.
Copper can act as a catalyst — meaning a substance that can speed up a chemical reaction and improve its efficiency. It does so by reducing the activation energy. Catalysts in biological reactions are called enzymes. Copper speeds up the reaction between zinc and dilute sulfuric acid.
It is found in some enzymes, one of which is involved in respiration. It really is a vital element! Go to the download section to access zip files of all resources for each subject and age group for use offline. Education Resources Copper: Properties and Applications. Copper has many extremely useful properties, including: good electrical conductivity good thermal conductivity corrosion resistance It is also: easy to alloy hygienic easily joined ductile tough non-magnetic attractive recyclable catalytic See below for more information on each of these properties, and how they benefit us in our daily lives.
Good Electrical Conductivity Copper has the best electrical conductivity of any metal, except silver. Copper coils can be found in: Device Use Electromagnets Locks, scrapyard cranes, electric bells. See Electromagnets. Motors Pumps, domestic appliances washing machines, dishwashers, fridges, vacuum cleaners , cars starter motors, windscreen wipers, electric windows , computers disc drives, fans , entertainment systems DVD players. See Electric Motors. Dynamos Bicycles, power stations Transformers Mains adaptors, electricity substations, power stations.
See Copper and Electricity: Transformers and the Grid. Conducting electricity We can connect a copper wire to a battery and a switch. This explains why: metals have electrical resistance.
Good Thermal Conductivity Copper is a good conductor of heat. These include: Device Use Copper plate Saucepan bottoms. Copper pipes Heat exchangers in hot water tanks, under floor heating systems, all weather football pitches and car radiators. Heat sinks Computers, disk drives, TV sets. A free electron collides with an ion at the hot end, and gains kinetic energy it speeds up. It moves to the cold end. This heats up the cold end. In this way, energy is transferred through copper, from hot to cold.
Corrosion Resistance Copper is low in the reactivity series. Alloys Easily Copper can be combined easily with other metals to make alloys.
Hygienic Copper is inherently hygienic, meaning it is hostile to bacteria, viruses and fungi that settle on its surface.
Easily Joined Copper can be joined easily by soldering or brazing. Ductile Copper is a ductile metal. Tough Copper and copper alloys are tough. Non-magnetic Copper is non-magnetic and non-sparking. Copper alloys turn out to be extremely useful for the exact same reason. It can be hammered or rolled into thin sheets and drawn into small wires without breaking. It is so conductive that 95 percent of all the transformers, cores of electrical wires, and other conductors are made of copper.
Durability — Most metals corrode as they oxidize. Iron, for instance, slowly reduces to rust when exposed to oxygen. Copper, on the other hand, oxidizes by developing a protective layer on its surface, called patina. The longer the exposure, the tougher the patina gets. This green layer of protection can preserve the inside of copper for thousands of years. Anti-Bacterial — Copper is also one of the few metals that can produce the oligodynamic effect, a phenomenon in which ions of copper break down certain proteins that make up single-celled organisms, killing them eventually.
Recyclable — Over 80 percent of all the copper ever mined and manufactured are still in use today, and they are all recyclable. Because of this, copper is considered one of the most eco-friendly metals.
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