Do you know how to tell whether a diamond certificate is genuine or forged?
The first thing is to master the characteristics. Judging from the reflection degree of fake diamonds, the reflection power is weak and the light is dark, that is, the flash power is not strong; Looking at it with a magnifying glass, the edges and corners of the grinder are round and easy to grind. Put it on the blue cloth, face down and point up, only one circle of the outer edge can't penetrate the blue below, and other parts reflect the blue below. If you hold it in your hand and look down from the tip, you can see all your fingerprints. The top surface of a real diamond has a strong photometric reflection, especially under strong light or sunlight, and its reflected color is bright and dazzling; The edges and corners of the grinder are sharp, and the sharp edges are not easy to wear. If you put it on blue, it won't reflect blue, and you can't see fingerprints on your hands.
Another method is to use the sharp edge of a real diamond, such as a drill knife. If you draw a deep groove, it is a fake diamond. You can't scratch a real diamond with a fake diamond. Real diamonds can't cross even if they cross. Ceylon diamond can cut glass, but it can only cut a shallow path. General merchants do not allow this kind of manipulation, so the safest way is to buy diamonds certified by national authorities in regular stores.
How to identify a formal diamond certificate?
Although the format of certificates issued by different diamond appraisal institutions is different, the main contents are basically the same. Generally, the measurement number, jewelry name, total weight including inlay and carrier, jewelry photos, appraiser's name, date of appraisal certificate and some qualitative or quantitative descriptions of different kinds of jewelry features will be marked. The book also indicates the name, identification marks, identification standards and norms of jewelry and jade appraisal institutions. Such a certificate can be used as an appraisal of ornaments.
Basic information of small 4C grading certificate
1. Diamond shape and specification (i.e. diamond size);
2. Carat weight, color grade, clarity grade and cut grade of diamonds;
3. Coordinates of diamond color grade, clarity grade and cut grade;
4. Signatures of raters and assessors, inspection date, etc.
Basic information contained in the big 4C diamond grade certificate
1. Diamond shape and specification (i.e. diamond size);
2. Carat weight, color grade, clarity grade and cut grade of diamonds;
3. Diamond proportion grade;
4. Coordinate map of diamond color code, coordinate map of clarity color code and schematic diagram of inclusion, coordinate map of section and projection map of section data, laser lettering photo of waist, eight diagrams, etc.
5. Signatures of raters and assessors, inspection date, etc.