Diamond is the hardest natural substance known, formed from pure carbon under extreme heat and pressure deep in the Earth’s mantle, renowned for its unparalleled brilliance, fire, and sparkle when expertly cut. Colorless in its purest form (though it can occur in fancy colors like yellow, pink, or blue), it rates a perfect 10 on the Mohs hardness scale, making it exceptionally durable. The ultimate symbol of eternal love and luxury, diamond is the traditional birthstone for April and the most coveted gemstone worldwide.