The definition of whether a person is beautiful or not is different in everyone's eyes, but since the Middle Ages we have used the "golden ratio" to express "beauty" uniformly. When it comes to diamonds, the "4C Rule" is the global diamond grading. Internationally recognized laboratories will print the diamond's 4C details on the certificate.
4C refers to: Carat, Clarity, Color and Cut.
Carat
Carat is "carat", and its English abbreviation is "ct". It refers to the weight of a diamond, but many people have regarded carat as the apparent size.
A 1-carat diamond weighs approximately 0.2 grams. At the same time, a 1-carat diamond is also called "100 parts." For example, a 0.3-carat diamond is called 30 parts, and a 0.7-carat diamond is called 70 parts.
When choosing the size of a diamond, you should consider the size of your finger and the various occasions it will be worn. What you should pursue when buying a diamond is the overall visual appearance. We usually observe the diamond from above to evaluate its size.
The carat of a diamond directly affects its price. The heavier the diamond, the higher the price, but it does not necessarily rise linearly. That is, diamonds of the same weight may also have huge differences, because the other 3C details of the diamond will affect its price.
Clarity
Diamonds often contain internal features called "inclusions" and external features called "blemishes." Diamonds with higher clarity have fewer, less noticeable inclusions and imperfections that enhance their overall brilliance and beauty.
Diamond clarity is divided into 6 levels:
- FL: Flawless
- IF: Internally Flawless
- VVS: Very Very Slightly Included
- VS: Very Slightly Included
- SI: Slightly Included
- I: Included level
Almost all diamonds contain flaws, and the flaws in FL and IF grade diamonds cannot be detected even under 10x magnification.
SI-level inclusions usually do not affect the sparkle and fire of diamonds, so many consumers also accept the use of SI-level diamonds for jewelry production. Generally, even inclusions are more popular.
Color
The color and transparency of a diamond are another important quality indicator. Because diamonds are mixed with a small amount of impurities, such as nitrogen, during the formation process, the diamonds contain a certain degree of hue, showing a light yellow color.
The following are the different grades of color:
- D grade: The highest color grade, which means the diamond is completely transparent and without any color.
- EF grade: colorless.
- Grade GJ: Slightly tinted, still considered a white diamond.
- KM grade: slightly yellow
- NZ grade: obvious brown tone
The color quality of DF grade is actually quite close, so it requires training and specific light sources to distinguish the difference between the two.
Cut
The cut of a diamond directly affects the visual size and sparkle of the diamond. Since the color and clarity are already determined, the cut is the second life of the diamond.
Cut ratings can be divided into three parts:
- Cut Grade: The scale ratio of each valve surface or position
- Polish: The polished smoothness of the surface
- Symmetry: neatness of cutting
The above three factors each have 5 levels: the highest is Excellent (Ex), then Very Good (VG), Good (G), Fair (F), and the lowest is Poor (P).