What is the diamond polished with?

Only diamonds can cut and grind diamonds.

Since a diamond is the hardest substance on earth, it can only be cut by another diamond. Therefore, diamond dust is used on the saw, and so is the actual diamond dust produced by cutting the crystal.

The saw used for diamond machining is a thin phosphor bronze disk, which rotates on a horizontal spindle at a speed of about 4000 rpm. The diamond is clamped, so it leans against the saw blade and saws for several hours according to the size of the diamond.

Diamond has high hardness, high refractive index and strong dispersion, and it is even more dazzling after careful carving.

Extended data:

The chemical composition of diamond is pure carbon (C) and its hardness is 10. Compared with Mohs hardness, diamond is the hardest, for example, ordinary glass is only 5 or 6. Diamond has high hardness, high refractive index and strong dispersion, and it is even more dazzling after careful carving.

Because the C-C bond in diamond is very strong, all valence electrons participate in the formation of covalent bonds, and there are no free electrons, so the diamond is not only hard, but also has a very high melting point and is not conductive.

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