Ore genesis and loses its metal carrying capacity. Ore deposits rarely fit neatly into the categories in which geologists wish to place them. Many may be formed by one or more of the basic genesis processes above, creating ambiguous classifications and much argument and conjecture. Often ore deposits are classified after examples of their type, for instance Broken Hill type lead-zinc-silver deposits or Carlin–type gold deposits. Classification of hydrothermal ore deposits is also achieved by classifying according to the temperature of formation, which roughly also correlates with particular mineralising fluids, mineral associations and structural styles. This scheme, proposed by Waldemar Lindgren (1933)
Galena, Illinois in 1863 and John Duerr was brevetted in 1865. Duerr later served as mayor of Monticello, Iowa. Galena Historical Society (June 21, 2006). "History Highlights". Retrieved April 13, 2007.www.galenahistorymuseum.org Galena, Illinois Galena is the largest city in and the county seat of Jo Daviess County, Illinois, with a population of 3,429 at the 2010 census. A section of the city is listed on the National Register of Historic Places as the Galena Historic District. The city is named for the mineral galena, which was mined by Native Americans in the area for over a thousand years. Owing to these deposits,