Minerals occur in different types of rocks. There are three types of rocks:
- Igneous rocks.
- Sedimentary rocks.
- Metamorphic rocks.
In igneous and metamorphic rocks, metallic minerals are found. Iron ore in North Sweden, copper and nickel deposits in Ontario Canada, iron, nickel, chromite and platinum in South Africa are examples of minerals found in igneous and metamorphic rocks.
Sedimentary rock formations of plains and young fold mountains contain non-metallic minerals like limestone.
For example, limestone deposits of Caucasus region of France, Manganese deposits of Georgia and Ukraine and phosphate beds of Algeria and mineral fuels like coal and petroleum are found in the sedimentary strata