Diamonds are the hardest natural substance on earth. Pure diamonds are colorless and transparent octahedral solids, and diamonds with impurities are brownish black. Because its hardness is higher than most substances in nature, it can be used to make cutting tools and easily cut high-hardness objects such as glass.

Among man-made materials, there are many substances harder than diamond, chromium and tungsten steel, such as carbon nitride, graphene and carbyne. These superhard substances usually do not exist naturally in nature. The hardness of carbon nitride is equal to that of diamond. Graphene, which is familiar to everyone, is harder than diamond. Carbyne is a newly invented artificial material in recent years, and it is the hardest material known on the earth.

The use of diamonds

Industrial use: Diamond is used to manufacture various cutting tools, such as saws, turning tools, milling cutters, wire drawing dies, scoring knives, etc. Diamonds are extremely hard and are ideal materials for making these tools.

Jewelry and decorations: Diamond is a precious gem, which is widely used to make jewelry and decorations because of its unique beauty and hardness.

Scientific research: Diamond is an excellent material, which can be used in various scientific research, such as high temperature and high pressure experiments and physical research.

Special materials: The high hardness and excellent physical properties of diamond make it an ideal material for making some special materials, such as superconducting materials and composite materials.

Optical instruments: Diamond has high refractive index and low dispersion, and is an ideal material for manufacturing optical instruments.

Aerospace and military applications: Diamond's high hardness and high temperature resistance make it an ideal material in aerospace and military fields, such as making windows for missiles and solar panels for satellites.