Hello, I'm a materials science enthusiast with a keen interest in the properties of various substances, including gemstones like diamonds. Let's delve into the question of diamond brittleness.

Diamonds are often considered the hardest known natural material. However, hardness and brittleness are not the same thing.
Hardness refers to a material's resistance to scratching or abrasion, while brittleness is a material's tendency to break without significant plastic deformation.

Diamonds, despite their extreme hardness, can be surprisingly brittle. This is because of their atomic structure, which is a tetrahedral lattice of carbon atoms. While this structure gives diamonds their incredible hardness, it also makes them susceptible to breaking along certain planes where the bonds are weaker. This is why diamonds can be cut and shaped using other diamonds—by exploiting these planes of weakness.

When a force is applied to a diamond, if it's along a plane where the bonds are weaker, the diamond can shatter. However, if the force is applied along a direction where the bonds are strongest, the diamond can withstand a significant amount of pressure.

In summary, while diamonds are the hardest substances, they are also brittle and can break under certain conditions.

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Diamonds are brittle precisely because they are so hard! Hardness is the ability of a material to resist plastic deformation. ... Atoms in diamond are held together by extremely strong covalent bonds, making them extremely hard. Because of this, diamond has no way of absorbing energy.read more >>