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Part of series of articles upon Archaeology of Kosovo. Copper Age sites in Kosovo Bronze Age sites in Kosovo Iron Age sites in Kosovo. The metal period incorporates a long stretched timeline of over three millennia, commencing from approximately 3500 BC up to middle of the 4th century BC.
Example of a copper alloy object: a Neo-Sumerian "Foundation Nail" of Gudea, circa 2100 BC, made in the lost-wax cast method, overall: 17.5 x 4.5 x 7.3 cm, probably from modern-day Iraq, now in the Cleveland Museum of Art (Cleveland, Ohio, USA) Copper alloys are metal alloys that have copper as their principal component.
Copper is sometimes used in decorative art, both in its elemental metal form and in compounds as pigments. Copper compounds are used as bacteriostatic agents, fungicides, and wood preservatives. Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the respiratory enzyme complex cytochrome c ...
Production trends in the top five copper-producing countries, 1950-2012. This is a list of countries by mined copper production. Copper ore can be exported to be smelted so that a nation's smelter production of copper can differ greatly from its mined production. See: List of countries by copper smelter production.
Copper was probably the first metal mined and crafted by humans. [8] It was originally obtained as a native metal and later from the smelting of ores. Earliest estimates of the discovery of copper suggest around 9000 BC in the Middle East. It was one of the most important materials to humans throughout the Chalcolithic and Bronze Ages.
Steel production (in million tons) by country as of 2023. The steel industry is often considered an indicator of economic progress, because of the critical role played by steel in infrastructural and overall economic development. [65] In 1980, there were more than 500,000 U.S. steelworkers. By 2000, the number of steelworkers had fallen to ...
Combining copper with tin and/or arsenic in the right proportions produces bronze, an alloy that is significantly harder than copper. The first copper/arsenic bronzes date from 4200 BC from Asia Minor. The Inca bronze alloys were also of this type. Arsenic is often an impurity in copper ores, so the discovery could have been made by accident.
Copper occurs in its native form in Chile, China, Mexico, Russia and the USA. Various natural ores of copper are: copper pyrites (CuFeS 2), cuprite or ruby copper (Cu 2 O), copper glance (Cu 2 S), malachite (Cu(OH) 2 CuCO 3), and azurite (Cu(OH) 2 2CuCO 3). Copper pyrite is the principal ore, and yields nearly 76% of the world production of copper.