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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.
Madrid | |
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State | |
Country | |
Capital | |
Population | 3233527 |
Madrid (, Spanish: [maˈðɾið]) is the capital and most-populous city of Spain. The city has almost 3.3 million inhabitants and a metropolitan area population of approximately 6.5 million. It is the second-largest city in the European Union (EU), surpassed only by Berlin, and its monocentric metropolitan area is the second-largest in the EU, surpassed only by Paris. The municipality covers 604.3 km2 (233.3 sq mi) geographical area.Madrid lies on the River Manzanares in the center of both the country and the Community of Madrid region, of which it is also the capital. As the capital city of Spain, seat of government, residence of the Spanish monarch, Madrid is also the political, economic and cultural centre of the country. The mayor is José Luis Martínez-Almeida from the People's Party.
The Madrid urban agglomeration has the third-largest GDP in the European Union and its influence in politics, education, entertainment, environment, media, fashion, science, culture, and the arts all contribute to its status as one of the world's major global cities. Madrid is home to two world-famous football clubs, Real Madrid and Atlético Madrid. Due to its economic output, high standard of living, and market size, Madrid is considered the major financial centre and the leading economic hub of the Iberian Peninsula and of Southern Europe. It hosts the head offices of the vast majority of major Spanish companies, such as Telefónica, IAG or Repsol.
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