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 Mountains in the vicinity of newly discovered ore deposits. Typical examples are the towns of Marienberg, Oberwiesenthal, Gottesgab ("Boží Dar"), Sebastiansberg ("Hora Sv. Šebestiána") and Platten ("Horní Blatná"). Economically, however, only silver and tin ores were used. From that time, the wealth of Saxony was built on the silver mines of the Ore Mountains. As a metal used for coinage, silver was minted on site in the mountain towns into money. The "Joachimsthaler" coins, minted in the valley of "Joachimsthal", became famous and gave their name to the medieval coin known as the "Thaler" from which the word "dollar" is