The hardest rock known to man is diamond. Diamonds are formed under high-pressure and high-temperature conditions deep within the Earth’s mantle. Composed entirely of carbon atoms arranged in a crystal lattice structure, they are renowned for their exceptional hardness and are ranked 10 on the Mohs scale of mineral hardness. This unique structure gives diamonds their ability to resist scratching and makes them incredibly valuable for industrial applications, particularly in cutting, grinding, and drilling. Beyond their industrial uses, diamonds are also highly sought after as gemstones in jewelry, celebrated for their brilliance and beauty.