Which Element Is Hardest?

The hardest pure element is carbon in the form of a diamond.

According to the reference, the hardest pure element known is carbon in its diamond form. This is because of the unique way carbon atoms bond together in a diamond's crystal lattice structure.

Let's break down why diamonds are so hard:

• Strong Covalent Bonds: Each carbon atom in a diamond is covalently bonded to four other carbon atoms in a tetrahedral arrangement. These covalent bonds are exceptionally strong and difficult to break.
• 3D Network Structure: This bonding extends throughout the entire diamond crystal, creating a rigid three-dimensional network. This network makes the structure incredibly resistant to scratching or deformation.

It is important to note that while diamond is the hardest element, hardness can also be affected by things such as impurities and microstructures. This makes certain synthesized materials that have been engineered with specific properties that may be able to outmatch diamond in hardness in some contexts.