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.
Nevada | |
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State | |
Country | |
Capital | |
Population | 0 |
Nevada (, Spanish: [neˈβaða]) is a state in the Western United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, the 19th-least populous, but the 9th-least densely populated of the U.S. states. Nearly three-quarters of Nevada's people live in Clark County, which contains the Las Vegas–Paradise metropolitan area, including three of the state's four largest incorporated cities. Nevada's capital is Carson City.
Nevada is officially known as the "Silver State" because of the importance of silver to its history and economy. It is also known as the "Battle Born State" because it achieved statehood during the Civil War (the words "Battle Born" also appear on the state flag); as the "Sagebrush State", for the native plant of the same name; and as the "Sage-hen State". The name means "snow-covered" in Spanish, referring to Nevada's small overlap with the Sierra Nevada mountain range; however, the rest of Nevada is largely desert and semi-arid, much of it within the Great Basin. Areas south of the Great Basin are within the Mojave Desert, while Lake Tahoe and the Sierra Nevada lie on the western edge. About 86% of the state's land is managed by various jurisdictions of the U.S. federal government, both civilian and military.American Indians of the Paiute, Shoshone, and Washoe tribes inhabited what is now Nevada. The first Europeans to explore the region were Spanish.