Ore genesis with igneous rocks. The world's major copper deposits are formed within the granitic porphyry copper style. Copper is enriched by processes during crystallisation of the granite and forms as chalcopyrite — a sulfide mineral, which is carried up with the granite. Sometimes granites erupt to surface as volcanoes, and copper mineralisation forms during this phase when the granite and volcanic rocks cool via hydrothermal circulation. Sedimentary copper forms within ocean basins in sedimentary rocks. Generally this forms by brine from deeply buried sediments discharging into the deep sea, and precipitating copper and often lead and zinc sulfides directly onto the
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