The hardest mineral found in nature is diamond. Composed entirely of carbon atoms arranged in a crystal lattice structure, diamonds have remarkable toughness and conductivity, which accounts for their unique properties. This extreme hardness makes diamonds valuable for various applications, particularly in cutting, grinding, and drilling tools. Beyond industrial uses, diamonds are highly sought after as gemstones in jewelry due to their brilliance and enduring nature. Their formation occurs deep within the Earth's mantle under high-pressure and high-temperature conditions over millions of years.