What is the hardest substance on the earth?

Answer 1

Aggregated Diamond Nanorods

ADNRs, are an allotrope of carbon believed to be the hardest and least compressible known material, as measured by its isothermal bulk modulus; aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), while a conventional diamond has a modulus of 442 GPa. ADNRs are also 0.3% denser than regular diamond.

The ADNR material is also harder than type IIa diamonds and ultrahard fullerite.

A process to produce the substance was discovered by physicists in Germany, led by Natalia Dubrovinskaia, at the University of Bayreuth in 2005.

ADNRs are made by compressing allotropic carbon fullerene molecules (generally 60 carbon atoms per molecule) to a pressure of 20 GPa, while at the same time heating to 2500 Kelvin, using a unique 5000 metric tonne multi anvil press. The resulting substance is a series of interconnected diamond nanorods, with diameters of between 5 and 20 nanometres and lengths of around 1 micrometre each.

They have used diamonds to cut steel.
Its diamond

Answer 2

The hardest substance currently known is Diamond, which is an allotrope of Carbon.

But the Hypothetical compound β-Carbon nitride, is thought to be more harder than Diamonds

Answer 3

It's not diamond anymore. Wurtzite Boron Nitride and Lonsdaleite

Answer 4

The hardest natural substance is the crystalized carbon known as diamond.

Answer 5

Carbon nanotubes and aggregated diamond nanorods; these are artificial materials.

As a natural crystal diamond is the hardest.

Answer 6

WATER

Answer 7

carbon

Answer 8

diamond