1. Clarity: Diamonds are the product of nature, the interior is more or less a few flaws, these flaws are diamonds in the growth process wrapped in the inside of the diamond's small crystals, clouds, needle points, small cracks. Clarity grade is a professional in 10 times times the magnifying glass, according to observe the size of the defect, how much and where the location, etc., divided into five major level 10 small class.
2. Color grading: Color grading is observed in the yellow series of diamonds in the apparent degree of yellow (brown) hue, the division of Diamond color level by professionals in a specific environment. The diamond color is divided into 12 levels, with English letters representing different color levels.
3. Cutting classification: Using the method of measuring and observing under the microscope, the quality of diamond cutting process is graded by the common ratio instrument. The degree of modification is the symmetry of diamond cutting and the evaluation of the quality of surface polishing. As a consumer, the quality of cut should be judged whether the diamond is bright, whether the fire color is obvious, the shape is symmetrical, the surface is damaged and so on several aspects.
4. Quality (commonly known as weight): is an important factor in evaluating the value of diamonds, the quality of the diamond Unit is grams (g), can also be used (CT), lg=5ct. In fact, most of the weighing is directly weighed with a carat balance, the carat value is reserved to two digits after the decimal point, and the third one does eight shekels in nine.