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
Western Ore Mountains Western Ore Mountains The Western Ore Mountains () is a natural region that forms the westernmost part of the Ore Mountains in the German federal state of Saxony. It is also part of the major landscape unit known as the Saxon Highlands and Uplands. It extends eastwards to include the valley of the Schwarzwasser, and, below its mouth, that of the Zwickauer Mulde, and incorporates the western parts of the former major units known as the Lower and Upper Western Ore Mountains ("Unteres und Oberes Westerzgebirge"), no. 423, as well as the Southern Slopes of the Ore Mountains ("Südabdachung des