Ore be processed and what ore is of too low a grade to be worth mining. Metal ores are generally oxides, sulfides, silicates, or native metals (such as native copper) that are not commonly concentrated in the Earth's crust, or noble metals (not usually forming compounds) such as gold. The ores must be processed to extract the elements of interest from the waste rock and from the ore minerals. Ore bodies are formed by a variety of geological processes. The process of ore formation is called ore genesis. An ore deposit is an accumulation of ore. This is distinct from a
Central Ore Mountains Central Ore Mountains The Central or Middle Ore Mountains ( or "Mittelerzgebirge") is a natural region that forms the central-western part of the Ore Mountains in the German federal state of Saxony. It is part of the overarching unit, the Saxon Highlands and Uplands. It forms the eastern part of the former major units, the Lower Western Ore Mountains ("Unteres Westerzgebirge", 423) and Upper Western Ore Mountains ("Oberes Westerzgebirge", 421) and is separated from the Eastern Ore Mountains in the east by the (included) valley of the Flöha, and from the Western Ore Mountains in the west by the (excluded)