7.Nickel ore

Any mineral ore from which nickel is obtained. The main minerals are arsenides such as chloanthite (NiAs2), and the sulphides millerite (NiS) and pentlandite ((Ni,Fe)9S8), the commonest ore. The chief nickel-producing countries are Canada, Russia, Kazakhstan, Cuba, and Australia.

8.Manganese Ore

The main ores are the oxides, such as pyrolusite, MnO₂; hausmannite, Mn₃O₄; and manganite, MnO(OH). Manganese ores may accumulate in metamorphic rocks or as sedimentary deposits, frequently forming nodules on the sea floor .The world's main producers are Georgia, Ukraine, South Africa, Brazil, Gabon, and India.