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.
Raleigh | |
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State | |
Country | |
Capital | |
Population | 0 |
Raleigh (; RAH-lee) is the capital of the state of North Carolina and the seat of Wake County in the United States. Raleigh is the second-largest city in the state, after Charlotte. Raleigh is known as the "City of Oaks" for its many oak trees, which line the streets in the heart of the city. The city covers a land area of 142.8 square miles (370 km2). The U.S. Census Bureau estimated the city's population as 474,069 as of July 1, 2019. It is one of the fastest-growing cities in the country. The city of Raleigh is named after Walter Raleigh, who established the lost Roanoke Colony in present-day Dare County.
Raleigh is home to North Carolina State University (NCSU) and is part of Research Triangle Park (RTP), together with Durham (home of Duke University and North Carolina Central University) and Chapel Hill (home of the University of North Carolina at Chapel Hill). The "Triangle" nickname originated after the 1959 creation of the Research Triangle Park, located in Durham and Wake counties, among the three cities and their universities. The Research Triangle region encompasses the U.S. Census Bureau's Raleigh-Durham-Chapel Hill Combined Statistical Area (CSA), which had an estimated population of 2,037,430 in 2013. The Raleigh metropolitan statistical area had an estimated population of 1,214,516 in 2013.
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