Slate Industry In Spain
Slate is a fine-grained, foliation (geology), foliated, homogeneous, metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcano, volcanic ash (volcanic), ash through low-grade, regional metamorphism. It is the finest-grained foliated metamorphic rock. Foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression. The foliation in slate, called "slaty cleavage", is caused by strong compression in which fine-grained clay forms flakes to regrow in planes perpendicular to the compression. When expertly "cut" by striking parallel to the foliation with a specialized tool in the quarry, many slates display a property called fissility (geology), fissility, forming smooth, flat sheets of stone which have long been used for roofing, floor tiles, and other purposes. Slate is frequently grey in color, especially when seen ''en masse'' covering roofs. However, slate o ...
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Minnesota
Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the south, and North Dakota and South Dakota to the west. It is the List of U.S. states and territories by area, 12th-largest U.S. state in area and the List of U.S. states and territories by population, 22nd-most populous, with about 5.8 million residents. Minnesota is known as the "Land of 10,000 Lakes"; it has 14,420 bodies of fresh water covering at least ten acres each. Roughly a third of the state is Forest cover by state and territory in the United States, forested. Much of the remainder is prairie and farmland. More than 60% of Minnesotans (about 3.71 million) live in the Minneapolis–Saint Paul metropolitan area, known as the "Twin Cities", which is Minnesota's main Politics of Minnesota, political, Economy of Minnesota, economic, and C ...
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