But it is difficult for ordinary consumers to grasp. I have some vivid metaphors here, which can make you clear at a glance. As the most precious gem at present, diamond has become the favorite of women for thousands of years with its hard quality and perfect refraction. The moment a woman puts on a diamond ring, the feeling of a happy life is beyond the reach of a careless man. Women love diamonds, men love diamonds, which comes from nature and the pursuit of beauty. The two are very similar. The following are the 4C standards for diamonds:
1. Diamond weight:
The weight of diamonds is calculated in carats, and 1 carat is equal to 100 cent, which is equal to 0.2 gram. For example, a 0.5-carat diamond can be written as 50 cents. Internationally, small drills with a score below 0.3 or 30, medium drills with a score between 30 and 50, and large drills with a score above 50. If the diamond is less than 30, other grades such as clarity are not necessarily so high. The weight of a diamond is the most important indicator of a diamond. A carat cut diamond needs to be excavated to obtain 250 tons of ore soil, which shows that diamonds are expensive. The weight of a diamond is equivalent to a girl's age, but conversely, the heavier a diamond is, the higher its value, and the opposite is true for a girl's age (just a joke metaphor, to strengthen her memory, please forgive me). It is easy to measure the weight of a diamond with a precision balance, but it is difficult to measure it accurately after it is inlaid with precious metals. The weight on the diamond certificate is the standard weight, that is, the weight indicated by the jeweler himself when the diamond is inlaid. Consumers must be careful. To buy large diamonds, you should choose honest sellers, not just cheap ones. After the diamond is inlaid, it is unrecognizable. Unless it is disassembled for identification, the certificate of diamond inlay products generally has the standard weight of diamonds: it refers to the marked weight of diamonds. It is not a specific weight appraisal, and consumers must have a clear understanding. Of course, I believe that most Taobao merchants are honest, but it does not rule out that some jewelry sellers are short of weight. They caught the customer's reluctance to dismantle the appraisal. The standard weight of diamonds does not match the reality, which harms the interests of consumers. First, don't simply seek cheap, learn more about the seller's word of mouth. This is always the case. If you get the same score, you sell them. Second: for more than 30 minutes, the jeweler must provide the certificate of rough diamond. The certificate of rough diamonds shows the weight of diamonds in great detail. As long as the appraisal institutions above the provincial level are very accurate and authoritative, the weight of the certificate of loose diamonds is very accurate, which is the same as buying them in shopping malls. Oh, this can effectively protect your interests. Don't worry, ordinary jewelers will provide certificates if they are honest.
2. Diamond clarity:
Schematic diagram of diamond clarity grade
FL-IF clarity: "FL" = flawless grade: the grade without inclusions or defects. A flawless diamond.
IF= internal level: there is no internal defect. For this grade of diamond, there are slight scratches on the outside of the diamond, but there are no flaws on the inside. These two kinds of clarity diamonds are extremely rare, but they are also the most beautiful.
VVS 1-2 cleanliness: extremely defective. The diamond clarity of VVS 1 grade is slightly better than that of VVS2 grade.
The definition of VS 1-2 is slightly defective. The diamond clarity of VS 1 is slightly better than that of VS2. These diamonds contain inclusions invisible to the naked eye. The price is a few points lower than the high-end clear. This kind of clarity grade diamond is very beautiful and of high value.
SI 1-2 cleanliness: slight defect. The diamond clarity of Si 1 grade is slightly better than that of SI2 grade. The contents of this clarity diamond can only be seen by professionals with a magnifying glass. This kind of clarity diamond has unique price and value.
P 1 clarity: these diamonds have obvious inclusions. Zakaly Jewelry classifies this grade of clarity diamonds as non-quality diamonds. Although you may find this kind of clarity grade diamonds in some places, Zakaly Jewelry does not recommend this kind of clarity grade diamonds.
Clear clarity.
Every diamond has inclusions, and the quantity, size, shape and color of inclusions will determine the purity and characteristics of each diamond. Most diamond inclusions used in jewelry are invisible to the naked eye. The less inclusions, the more light is refracted, making it doubly bright. The purity of diamonds is equivalent to that of girls. It's just a joke here, and there is absolutely no other meaning. I hope JMS understands, so it's easy to remember. Every man always wants his girlfriend to be the first time when he is in love, with no past, no history and infinite purity. It's a pity that kindergartens are looking for such girls now. Moderate enough, as long as he is loyal to you, some defects are acceptable. We can use a magnifying glass with a magnification of 10 to enlarge them respectively. The classification standards of cleanliness are: FL, IF(LC), VVS, VS, SI, P. (Note: LC is the best, and it decreases in turn. Generally, there are VVS, VS and SI circulating in the market, and the United States subdivides the definition into VVS 1, VVS2 and so on. ) Our domestic testing stations are the strictest and most standard in identifying the clarity of diamonds, because they all rely on microscopes. Relatively speaking, the level of clarity in Hong Kong is much looser. Many domestic SI and P diamonds are wholesale to Hong Kong, which in turn can be identified as VS or above and sold to mainlanders. Now domestic diamonds will be refunded soon. The cost of diamonds is the same as that of Hong Kong. Hong Kong diamonds are cut and set in China. At present, more than 90% diamond jewelry inlay factories in China are located in Shenzhen, and Hong Kong's artificial land rent can't process jewelry. If you buy goods from Shenzhen, the labor and wages in Hong Kong will not be cheaper than those in the Mainland. Some time ago, the national inspection spot-checked diamonds, and the unqualified bare diamonds in Zhou Shengsheng were exposed, which was not an independent incident. This is an open secret among jewelers in Hong Kong, and the cleanliness is generally low. And then sold to mainlanders, who traditionally think that Hong Kong diamonds are cheap.
3. The color of the diamond
Color color
Most diamonds can be divided into "colorless and transparent" to "nearly colorless", of which the highest color "colorless and transparent" is named after the English word "D" until Z-colored "light yellow" diamonds. "Colorless and transparent" diamonds are extremely precious and rare, and "nearly colorless" to "light yellow" are more common. Diamonds are the color of a girl's skin. The whiter, the more expensive. The higher the color of a carat diamond, the higher the price. The color of diamonds is very important. The color of a diamond is mostly I-J in domestic shopping malls, and there are also some colors of K-L and H. Basically, it is rare to see anything above F-G color and below M-N color, because jewelry merchants have high costs above H color. The color is too low and obvious to the naked eye, so there are too many I-J colors, especially diamonds. In our country, color is more important than clarity to some extent. Our country is obvious. In Shanghai in the south, the clarity can be reduced and SI is acceptable. The color must be above H, but Beijing and most mainland provinces are uncertain about the color, so it must be VVS, at least above VS, and the color I-J presents a very uneven distribution. In fact, it is a matter of confidence, and it is enough to be moderate according to your own budget. Because the color of diamonds needs to be compared with colored stones, a set of standard colored stones is very expensive, and many small detection stations are not objective enough to detect colors.
The specific grading method is to visually compare the sample with a set of standard circular drill samples (7- 10) with calibrated color scale.
Conditions: It is carried out in an indoor environment without direct sunlight (only the window facing north is opened in the trading hall in the northern hemisphere), the surrounding color is white or gray, the color temperature of the grading lamp is 5000 K-7200 K (6500K stipulated by Belgium), and the color grading of the same sample is independently completed by 2-3 people who have been trained in special skills, and unified results are obtained.
It should be noted that the "white" of diamond color actually means colorless and transparent (white light is not absorbed and reflected, but completely transmitted), and the saturation is zero. "White" in the physical sense should mean that white light is not absorbed but totally reflected.
Generally, certificates from national and international institutions should be issued, such as national inspection (national inspection in Huang Zhuang, Beijing), GIA, China Geo University; If it is a big diamond, you must issue a certificate of bare diamond to ensure your interests to the greatest extent.