Cobalt | |
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State | Ontario |
Country | Canada |
Capital | |
Population | 1128 |
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.
Hamburg | |
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State | |
Country | |
Capital | |
Population | 0 |
Hamburg (English: , German: [ˈhambʊʁk] (listen), locally also [ˈhambʊɪ̯ç] (listen); Low Saxon: Hamborg [ˈhambɔːç] (listen)), officially the Free and Hanseatic City of Hamburg (German: Freie und Hansestadt Hamburg; Low Saxon: Friee un Hansestadt Hamborg), is the second-largest city in Germany after Berlin and 7th largest city in the European Union with a population of over 1.84 million.One of Germany's 16 federal states, it is surrounded by Schleswig-Holstein to the north and Lower Saxony to the south. The city's metropolitan region is home to more than five million people. Hamburg lies on the River Elbe and two of its tributaries, the River Alster and the River Bille.
The official name reflects Hamburg's history as a member of the medieval Hanseatic League and a free imperial city of the Holy Roman Empire. Before the 1871 Unification of Germany, it was a fully sovereign city state, and before 1919 formed a civic republic headed constitutionally by a class of hereditary grand burghers or Hanseaten. Beset by disasters such as the Great Fire of Hamburg, North Sea flood of 1962 and military conflicts including World War II bombing raids, the city has managed to recover and emerge wealthier after each catastrophe.
Hamburg is Europe's third-largest port. Major regional broadcaster NDR, the printing and publishing firm Gruner + Jahr and the newspapers Der Spiegel and Die Zeit are based in the city. Hamburg is the seat of Germany's oldest stock exchange and the world's oldest merchant bank, Berenberg Bank. Media, commercial, logistical, and industrial firms with significant locations in the city include multinationals Airbus, Blohm + Voss, Aurubis, Beiersdorf, and Unilever.
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