Rare metal ores /reər ˈmɛtəl ɔrz/ – natural mineral formations containing rare elements in the form of independent minerals or isomorphic impurities dispersed in ore and vein minerals in quantities sufficient for their cost-effective industrial extraction. Elements classified as rare make up almost half of Mendeleev’s periodic table of elements, although they make up about 0.2% of the earth’s crust.
Ex. The exploration team discovered a new deposit rich in rare metal ores, including tantalum and niobium.