Diamond 4C grading

    Date:  2016-09-06Author:  ZENITH

Analyzing the 4C diamond quality grading criteria are: Carat Weight, Colour, Clarity and Cut.

1, Carat Weight. Diamond carat weight in the calculation. Ancient times people in order to contrast the weight of diamonds: 1 kt = 0.2 grams. 1 kt divided into 100 parts, called every 1 minute. Internationally recognized hedge diamond weight of 0.40 carats.

2, Colour. Color grading standards: D (100), E (99), F (98), G (97), H (96), I (95), J (94); D-I as a white tone, J less apparent see yellow tone.


3, Clarity. Cleanliness diamond is the result of dedicated professional gemologists at 10 times the magnifying glass as the basis. It includes two aspects, namely, the destruction of the original gemstone internal defects and processing of the diamond surface caused. Under a magnifying glass to see the defects not rare diamonds, diamond clarity grade is subdivided into: FL (no defect), VVS (very, very minor flaws), VS (very small defects), SI (slight imperfections ), I (unclean). Wherein VVS to SI level flaw is invisible; Class I defect to the naked eye can see.

4, Cut. Cut refers to the angles and proportions of technicians in the process of converting raw diamonds into polished diamonds in the cutting. Cut is good or bad is determined by the intensity of the color of fire diamonds. Good cut diamond reflected the dazzling bright color of fire, cut poor diamonds reflected the dim color of fire. The main index cut grading are: the percentage of countertops, crown angle, depth percentage bottom, waist thickness, the bottom tip sizes, the degree of modification (polishing degree and degree of symmetry). Divided into good, good, fair categories.

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