Which types of rocks can contain ore deposits?

Ore deposits can be found in all three major types of rocks: igneous, sedimentary, and metamorphic.1

• Igneous rocks: These deposits often form through magmatic processes, such as the early crystallization of minerals from a melt, which then concentrate into bodies within the rock.12
• Sedimentary rocks: These deposits are typically formed at the Earth's surface through processes like evaporation or the accumulation of minerals in layers, such as the vast Precambrian iron ore deposits.1
• Metamorphic rocks: Ore deposits in these rocks often have complex origins, where minerals may have been present in the original sedimentary rock or introduced later by circulating solutions during the metamorphic process.1

Additionally, minerals can be deposited from hydrothermal solutions that flow through fractures and open spaces within various rock types. While ore deposits are found in both continental and oceanic rocks, current mining operations are restricted to those located within the continental crust.23