Iron oxide copper gold ore deposits to be within Neoproterozoic to Mesoproterozoic basement. Worldwide, ages of recognised IOCG deposits range from 1.8 Ga to 15 Ma, however, the majority are within the 1.6 Ga to 850 Ma range. Ore minerals in IOCG deposits are typically copper-iron sulfide chalcopyrite and gangue pyrite, forming 10–15% of the rock mass. Supergene profiles can be developed above weathered examples of IOCG deposits, as exemplified by the Sossego deposit, Para State, Brazil, where typical oxidised copper minerals are present, e.g.; malachite, cuprite, native copper and minor amounts of digenite and chalcocite. Alteration is a mixture of sodic-calcic (albite-epidote) to potassic (K-feldspar)
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