Galena, Kansas taking the present name of Galena in 1877, which is named after the lead ore galena found in the area. The city was part of the tri state mining area and had over 30,000 inhabitants. After the mines closed in the 1970s, population decreased. The Jayhawk Ordnance Works northwest of Galena, built during World War II, was a large ordnance plant producing ammonium nitrate. After the war it was privatized by its operator Kenneth Aldred Spencer and at one point was the world's largest producer of ammonium nitrate fertilizer in the world. It would form the basis for the Spencer
Ore genesis classified hydrothermal deposits as "hypothermal", "mesothermal", "epithermal", and "telethermal". Epithermal deposits are hydrothermal ore deposits formed at low temperatures (50-200 °C) near the Earth´s surface (<1500 m), that fill veins, breccias, and stockworks. The age of formation of epithermal deposits in México is currently being investigated. "As they require the conjunction of specific environmental conditions to form, particular mineral deposit types tend to occupy specific geodynamic niches," therefore, this page has been organised by metal commodity. It is also possible to organise theories the other way, namely according to geological criteria of formation. Often ores of the same metal can