Diamonds are commonly known as "Jin Gangzuan". That is, we often say that the original diamond is a mineral composed of carbon, which is an allotrope of carbon. Diamond is the hardest substance in nature. It is a colorless crystal made of carbon, and its hardness is second only to that of blue diamond. Diamonds are widely used, such as handicrafts and industrial cutting tools. Graphite can form synthetic diamond at high temperature and high pressure. It is also a precious stone.

20 18, 18 In February, a yellow diamond weighing 552 carats was unearthed in Canada, making it the largest diamond found in North America.

Hardness:

Mohs hardness 10, new Mohs hardness 15, microhardness 10000kg/mm, microhardness is 1000 times higher than that of the corresponding time and 150 times higher than that of corundum. The hardness of diamond is directional. The hardness of octahedral crystal face is greater than that of rhombohedral crystal face, and the hardness of rhombohedral crystal face is greater than that of hexahedral crystal face.

According to Mohs hardness scale, it is divided into 10 grade, with diamond as the highest grade and 10 grade. For example, the hardness of knives is about 5.5, copper coins are about 3.5 to 4, nails are about 2 to 3, and the hardness of glass is 6.

Because of the highest hardness, diamond powder or laser (such as 532nm or 1064nm wavelength laser) must be used for diamond cutting. The density of diamond is 3.52 g/cm, the refractive index is 2.4 17 (at 500 nm) and the dispersion rate is 0.044.