The hardest natural mineral is diamond. Composed of carbon atoms arranged in a crystal lattice structure, diamonds boast extraordinary hardness, which is measured by the Mohs scale at a level of 10. This unique property makes diamonds highly sought after for industrial applications, especially in cutting, grinding, and drilling. Moreover, diamonds’ exceptional brilliance and fire have made them valuable as gemstones in jewelry. The natural formation of diamonds occurs deep within the Earth's mantle under extreme pressure and temperature, and they are often found in volcanic rock formations called kimberlites.