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
Ore Mountains out Germany-wide in the 1950s the Ore Mountains formed major unit group 42: Even after the reclassification of natural regions by the Federal Agency for Nature Conservation in 1994 the Ore Mountains, region "D16", remained a major unit group with almost unchanged boundaries. However, at the beginning of the 21st century, the working group "Naturhaushalt und Gebietscharakter" of the Saxon Academy of Sciences ("Sächsische Akademie der Wissenschaften") in Leipzig merged the Ore Mountains with the major unit group of Vogtland to the west and the major landscape units of Saxon Switzerland, Lusatian Highlands and Zittau Mountains to the east into