Diamonds 4c refer to the following four points respectively: weight, the greater the weight, the rarer the diamond, and the higher the value; Clarity, diamond clarity is divided into six grades: FL, IF, VVS, VS, SI, I * * * cut, and diamond cut can be divided into five grades: EX, VG, G, F and P; Color, diamond color can be divided into D ~ Z * * * 23 grades.

Weight is one of the 4c standards of diamonds. The unit of weight of diamonds is carats. Most of the common diamonds in life are below 1 carat. The heavier the diamond, the rarer it will be and the higher its value will be.

Clarity refers to the visual cleanliness of diamonds. According to the number of surface defects and inclusions seen by a diamond under a magnifying glass of ten times, it can be divided into six grades: FL, IF, VVS, VS, SI and I * * * *.

The cutting of cut diamonds is divided into three aspects: cutting proportion, grinding and symmetry, and each aspect is divided into five grades: EX, VG, G, F and P. The best cutting requires all three to reach the EX grade, which is referred to as "3EX" in the industry.

The color of colored diamonds can be divided into 23 grades from colorless to light yellow, among which D-grade diamonds are the best in color, colorless and transparent, and the closer they are to colorless diamonds, the higher their value will be.