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)
Mineral industry of Armenia precious metal mines. Among these mines, about 400 mines, including 22 base metal, non-ferrous metal and precious metal mines are currently being exploited. Among the base metal and precious metal deposits, there are 7 copper-molybdenum mines, 3 copper mines, 13 gold and gold-polymetallic mines, 2 polymetalilc mines and 2 iron ore mines. In addition to those mines registered in the state inventory of mineral resources, there are an additional 115 deposits of various deposits that have been discovered. In 2017 mining industry output with grew by 14.2% to 172 billion AMD at current prices and run at 3.1% of Armenia's