The hardest naturally occurring mineral on Earth is diamond. Formed under high-pressure and high-temperature conditions deep within the Earth's mantle, diamonds are composed of carbon atoms arranged in a crystal lattice structure. This unique arrangement gives diamonds their exceptional hardness and ability to scratch other materials. Beyond their geological significance, diamonds are highly valued for their use in jewelry and industrial applications, such as cutting tools and abrasives. Their durability and brilliance make them not only the hardest mineral but also symbols of luxury and status in many cultures.