Weight: The weight of diamonds is calculated in carats, 1 carat = 0.2g = 100 minutes. Internationally recognized diamonds weigh more than 0.40 carats, while our country weighs more than 0.30 carats. Generally speaking, the heavier the diamond, the higher the price.

Color: Colorless is the best color for diamonds (except colored diamond). The darker the hue, the worse the quality. The colors from high to low are: D, E, F, G, H, I, J, K, L, M, N ... The more expensive it is.

Cleanliness: the cleanliness of a diamond refers to the cleanliness of a diamond, that is, how many impurities a diamond contains, which needs to be observed and judged by a professional gemologist under a special magnifying glass with a magnification of 10. The clarity of diamonds from good to bad is FL, IF, VVS 1, VVS2, VS 1, VS2, SI 1, SI2, SI3, I. The more expensive the front, the diamond ornaments and pendants are generally treated with cleanliness above SI.

Cutting: Cutting refers to the angle and proportion cut by experienced technicians in the process of transforming diamond raw materials into polished diamonds. Cutting is the only part of 4c that can be directly controlled by manpower, which greatly affects the fire color and brightness of diamonds, thus affecting the price. Cutting is divided into EX+, EX, VG+, VG, G, general and poor grades. EX+ is the best cutting, and the worse it is. The fire reflected by the cut diamond is bright and dazzling, while the fire reflected by the cut diamond is dim.

Many people don't know that in addition to these four C's, there is another important factor that affects the price of diamonds, and that is fluorescence. The fluorescence levels are divided into VS, S, Med, F and Non. The stronger the front fluorescence, the cheaper the price. Diamonds with strong fluorescence will have poor permeability under light irradiation. Particularly strong fluorescence will affect the price of diamonds by more than 35%.