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.
Malmö | |
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State | |
Country | |
Capital | |
Population | 0 |
Malmö (; Swedish: [ˈmâlmøː] (listen); Danish: Malmø [ˈmælmˌøˀ]) is the largest city in the Swedish county (län) of Scania. It is the third-largest city in Sweden, after Stockholm and Gothenburg, and the sixth-largest city in Scandinavia, with a population of 316,588 (municipal total 338,230 in 2018). The Malmö Metropolitan Region is home to over 700,000 people, and the Öresund region, which includes Malmö, is home to 4 million people.Malmö was one of the earliest and most industrialized towns in Scandinavia, but it struggled to adapt to post-industrialism.