Hardest Substance on Earth
The hardest substance on Earth is diamond.

Composition of Diamond
- Diamond is composed of carbon atoms arranged in a strong crystal lattice structure.
- Each carbon atom in a diamond is bonded to four other carbon atoms in a tetrahedral structure.

Hardness of Diamond
- Diamond is known for its exceptional hardness, scoring a perfect 10 on the Mohs scale of mineral hardness.
- The Mohs scale is a scale ranging from 1 (softest) to 10 (hardest) that measures a mineral's resistance to scratching.

Properties of Diamond
- Diamond is extremely durable and has a high thermal conductivity.
- It is also transparent, allowing light to pass through and creating a brilliant sparkle.

Uses of Diamond
- Due to its hardness and durability, diamond is commonly used in cutting, grinding, and polishing tools.
- It is also used in jewelry, particularly in engagement rings and other high-end pieces.
In conclusion, diamond stands out as the hardest substance on Earth due to its unique crystal structure and exceptional properties.