There are four classification criteria for diamond grades, namely, diamond purity grade, diamond carat grade, diamond color grade and diamond cutting grade. Diamond purity can be divided into five grades: F to I, and F and IF are the best grades, almost transparent, very precious and rare. Generally sold in stores, VVS 1 and VVS2 are high-end products. Followed by SI 1 and SI2. Then I 1, I2, I3. -Quoted from the Internet

I 1, I2 and I3 diamonds have obvious impurities. Not all diamonds can fetch high prices. Diamonds below I 1 are basically the cheapest among diamonds, and you can buy them for hundreds of dollars. If you want to use it as an ornament or a collectible, you should at least buy diamonds with a purity of VVS 1 or above, and the diamonds sold by jewelry stores are also above this level.

Carat is the international unit for measuring the weight of diamonds. A diamond-Klajo is 0.2g, and there is also the concept of carat in other precious stones. The density of diamonds is relatively stable. The more carats, the bigger the volume, the rarer the natural diamonds, and the higher the price. Diamonds over one carat have collectible value and investment attributes.

The color grade of diamond can be divided into five grades from D-Z, and the diamond cutting can be divided into six grades. The following four criteria for measuring diamonds are actually the 4C criteria we usually hear. The diamond shop appraisal certificate sold by jewelry stores will indicate the 4C standard of diamonds, which is the most important basis for consumers to choose diamonds. Each dimension has multiple grades, among which the number of carats of diamonds has the greatest influence on the price and quality of diamonds.