A one carat diamond weighs 0.2 grams. According to the conversion of diamond units from carat to gram: 1 carat=0.2 grams=200 milligrams, this measurement standard has been in use since 1907 when carat was internationally agreed as the unit of measurement for gemstones such as gemstones and diamonds. A one carat diamond is relatively rare in the market, and high-quality one carat diamonds are also very expensive.
Diamond grading
The grade of diamonds is generally classified according to the 4C standard. The so-called 4C refers to the color, clarity, weight, and cut of diamonds. These four aspects collectively determine the quality of diamonds.
1. Color
GIA divides the color range of diamonds from colorless to light yellow or light brown into 23 consecutive color levels, represented by the letters D, E, F, G, H, I, J, K, L, M, N, O, Q, R, S, T, U, V, W, X, Y, and Z from high to low.
2. Clarity
Diamonds are naturally formed, and even though they may appear smooth and translucent, they often have some natural flaws inside to varying degrees. Just like the cotton wool or black spots inside jade, this is very normal.
So the clarity of diamonds is actually an indicator used to measure the internal flaws of diamonds. It uses a standard 10x magnifying glass to observe the degree of internal and external flaws in diamonds, and the higher the clarity level, the better the transparency and quality.
The GIA cleanliness grading system has 11 cleanliness levels, which are FL IF、VVS1、VVS2、VS1、VS2、SI1、SI2、I1、I2、I3。
Under 10x magnification, no internal or external features were observed in the diamond, which can be further divided into FL IF；
Under a 10x magnifying glass, diamonds exhibit extremely small internal and external features, subdivided into VVS1 VVS2；
Under a 10x magnifying glass, diamonds exhibit small internal and external features, subdivided into VS1 VS2；
Under a 10x magnifying glass, diamonds exhibit distinct internal and external features, subdivided into SI1 SI2；
From the crown observation, visible to the naked eye, diamonds have internal and external features, which are subdivided into I1 I2、I3。
3. Cutting off
A circular diamond cutter typically consists of 57 facets, including the crown, crown, and waist ridge; Crown angle, pavilion angle, platform width ratio, pavilion depth ratio, waist thickness ratio, etc.
The cutting levels of GIA are divided into five levels: EX (Excellent), VG (Very Good), G (Good), F (Faint), and P (Poor).
The cutting level also includes five polishing levels: EX (Excellent), VG (Very Good), G (Good), F (Faint), and P (Poor)
The cutting level also includes five levels of symmetry: EX (Excellent), VG (Very Good), G (Good), F (Faint), and P (Poor)
4. Kela
