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Mining Districts of Montana, developed by the Montana Abandoned Mines Reclamation Bureau. Based on a map of minining districts (called Memoir 15) made in 1935, with some districts revised or removed, with addtional districts added. The districts were revised again in May of 1995.
Mining districts were formed by associations of miners in a region who developed rules and laws to govern mining in the district. They sometimes established a monument to serve as the reference point for surveys in the district and created a description of the district boundary. Mining districts are no longer legal entities. Historical narratives describing the mining districts and their boundaries are available from the Montana Department of Environmental Quality.
The layer contains a field called Type that has values of M15 to designate Memoir 15 districts that existed in 1935, M15I to designate districts that were formed by merger of a Memoir 15 district with another district, and NEW to designate districts created after 1935. The layer contains a field called AKA that contains lists of other names that districts were "also known as". |