Cobalt vs Dunedin

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Cobalt is a chemical element with the symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal. Cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was later thought to be due to the known metal bismuth. Miners had long used the name kobold ore (German for goblin ore) for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the kobold. Today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as cobaltite (CoAsS). The element is, however, more usually produced as a by-product of copper and nickel mining.

The copper belt in the Democratic Republic of the Congo (DRC) and Zambia yields most of the global cobalt production. World production in 2016 was 116,000 metric tons (114,000 long tons; 128,000 short tons) (according to Natural Resources Canada), and the DRC alone accounted for more than 50%.Cobalt is primarily used in lithium-ion batteries, and in the manufacture of magnetic, wear-resistant and high-strength alloys. The compounds cobalt silicate and cobalt(II) aluminate (CoAl2O4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays. Cobalt is the active center of a group of coenzymes called cobalamins. Vitamin B12, the best-known example of the type, is an essential vitamin for all animals. Cobalt in inorganic form is also a micronutrient for bacteria, algae, and fungi.

Source: Wikipedia

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Dunedin ( (listen) duh-NEE-din; Māori: Ōtepoti) is the second-largest city in the South Island of New Zealand (after Christchurch), and the principal city of the Otago region. Its name comes from Dùn Èideann, the Scottish Gaelic name for Edinburgh, the capital of Scotland.The urban area of Dunedin lies on the central-eastern coast of Otago, surrounding the head of Otago Harbour, and the harbour and hills around Dunedin are the remnants of an extinct volcano. The city suburbs extend out into the surrounding valleys and hills, onto the isthmus of the Otago Peninsula, and along the shores of the Otago Harbour and the Pacific Ocean. Dunedin was the largest New Zealand city by territorial land area until superseded by Auckland with the formation of the Auckland Council in November 2010. Archaeological evidence points to lengthy occupation of the area by Māori prior to the arrival of Europeans. The province and region of Otago takes its name from the Ngāi Tahu village of Otakou at the mouth of the harbour, which became a whaling station in the 1830s. In 1848 a Scottish settlement was established by the Lay Association of the Free Church of Scotland. Between 1855 and 1900 many thousands of Scots emigrated to the incorporated city.

Dunedin became wealthy during the Central Otago Gold Rush, beginning in the 1860s. In the mid-1860s, and between 1878 and 1881, it was New Zealand's largest urban area. The city population at 5 March 2013 was 120,246. While Hamilton, Tauranga and Lower Hutt have eclipsed the city in size of population since the 1980s to make it only the seventh-largest urban area in New Zealand, Dunedin is still considered one of the four main cities of New Zealand for historic, cultural and geographic reasons.Dunedin has a diverse economy, which includes manufacturing, publishing and technology-based industries as well as education, research and tourism. The city's most important activity centres around tertiary education—Dunedin is home to the University of Otago, New Zealand's oldest university (established 1869), and the Otago Polytechnic. Students account for a large proportion of the population; 21.6 per cent of the city's population was aged between 15 and 24 at the 2006 census, compared to the New Zealand average of 14.2 per cent. In 2014 Dunedin was designated as a UNESCO City of Literature.

Source: Wikipedia