General Knowledge - General Science - Discussion

Diamonds have strong covalent bond.

Because of its tripod structure and strong carbon bonds.

It is the hardest mineral.
It is also used to cut glass.
It is a non-metallic mineral.

Presently the hardest substance is wurtzite boron nitride.

I think it would be boron carbide.

Boron carbide is third after diamond and cubic boron carbide.

Because of very strong sigma bond between each carbon atom.

Only a diamond can cut the other diamond.

Yes, wurtzite boron nitride (w-BN) is indeed harder than diamond under certain conditions. When subjected to high pressures, wurtzite boron nitride can exceed the hardness of diamonds by about 18%. This increased hardness is due to a unique atomic bond rearrangement that occurs under stress.

However, it’s important to note that this extreme hardness is not permanent and is observed only under specific conditions.
Another material, lonsdaleite (hexagonal diamond) , has also been found to be harder than both diamond and wurtzite boron nitride.