Diamonds weighing less than 1 carat are usually measured in "points", 1 carat = 100 carat. On the certificate of diamond, the weight of diamond is accurate to the third decimal place.
Carat, as a unit of weight, originated from the seeds of Oryza sativa L. on the Mediterranean coast of Europe, with red flowers and brown nuts in pods, about 15cm long, which can be used to make glue.
There is a strange phenomenon in carob trees. No matter where it grows, it bears the same weight of nuts. Historically, this fruit has been used as a weight to measure weight. Over time, it has become a unit of weight for weighing precious and subtle substances. It was not until 1907 that it was internationally recognized as a unit of measurement for gems, and it is still in use today.
Extended data:
Carat (ct), usually abbreviated as Ct, has been used as an internationally recognized unit of measurement for gemstones since 1907. CT is the quality unit of jade, diamond and other precious stones, and it is the purity ratio of precious metals. International standard 4C for evaluating diamonds. 4C refers to color, clarity, weight and cut.
1 carat can be divided into 100 minutes, which can be calculated as a relatively small gem. Because the density of diamonds is basically the same, the heavier the diamond, the bigger the volume. The bigger the diamond, the rarer it is, and the higher the value per carat.
The metric carat unit, that is, 1 carat equals 200mg, is adopted from 1907. Before that, one carat was equal to 205.3 mg, or 0.2053 g.
The price of a diamond ring is calculated in carats. Generally, 0.2 carat sells for about 4000 yuan; 0.3 carat sells for about 7000 yuan, and the bigger it is, the more expensive it is. Beautiful diamonds depend on purity, whether there are cracks, how many cracks, color, cutting and so on. The price is related to the above points! Purity, luster, weight, size, color (the purer the better), exquisite workmanship, it is generally impossible to see that it is a diamond without polishing.
Know little about diamonds;
1. The higher the diamond grade, the greater the influence of the weight on the price.
2, especially for diamonds with critical weight. Such as: 30 minutes, 40 minutes, 50 minutes, 1 carat, etc.
3, less than 0.2 carat national standard is not classified. 0.2 to 1 carat can be classified by both loose diamonds and inlaid diamonds. Diamonds larger than 1 carat must be classified by 4C according to the classification standard for loose diamonds.
How to choose a diamond ring:
Generally speaking, it is more appropriate to choose a diamond-encrusted ring below 50 points, which can not only express love but also be accepted by people of the general income class. A single diamond ring of 30 to 40 cents is a common choice for white-collar workers. Some rings inlaid with broken diamonds are also loved by some people because of their exquisite design.
If economic conditions permit, it is best to choose diamonds with a score of more than 50, because diamonds with a score of more than 50 have considerable ability to maintain and increase value and have certain investment value.
While paying attention to the weight of diamonds, we must pay attention to the color, clarity and cut of diamonds, that is, comprehensively consider the "4c" standard. Diamonds with large weight, good cutting (bright light), few pure defects and white color are good diamonds.
When buying diamond jewelry with a score of more than 30 points, don't forget to ask the merchant to show the appraisal certificate of the national testing department. In addition, it is suggested that when buying a diamond ring, it is best to buy earrings and pendants that can match it, so as to avoid regrets caused by improper matching of jewelry.
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