Diamond and graphite are both allotropes of carbon, meaning they are made of the same element—carbon—but have different atomic arrangements, leading to vastly different physical properties.

In diamond, each carbon atom is bonded to four other carbon atoms in a three-dimensional tetrahedral structure, creating an extremely hard and rigid crystal. This makes diamond the hardest natural substance known, with excellent light dispersion and thermal conductivity.

In contrast, graphite has a structure where each carbon atom is bonded to three others in flat hexagonal sheets. These layers are held together by weak van der Waals forces, allowing them to slide over each other easily, making graphite soft, slippery, and an excellent electrical conductor.

Despite being composed of the same element, these allotropes demonstrate how atomic structure alone can dramatically alter a substance’s properties.