Diamonds are the hardest known natural material, with a rating of 10 on the Mohs Hardness Scale. This means that nothing else found in nature can scratch a diamond.
However, there are some materials that have been created in a lab that are harder than diamonds, such as:
* Lonsdaleite: A hexagonal form of carbon, sometimes called "hexagonal diamond."
* Wurtzite boron nitride: Another material with a hexagonal structure, similar to lonsdaleite.
While these materials are harder than diamonds, they are extremely rare and not found naturally.
