Oiliness test: use a special pen or ballpoint pen dipped in oily ink to draw a line on the diamond table, which will leave an uninterrupted straight line. However, other imitations are not lipophilic, leaving intermittent dotted lines at the scribe line.

Water drop test: the water drops on the diamond will remain spherical for a long time, while the water drops on the imitation will disperse in a short time.

Breathing test: breathe into the diamond, if the water vapor on the diamond disappears, it will become a real diamond immediately; If the water vapor stays on the diamond for a few seconds and then disappears, it is a fake diamond.

Sensory test: There is a very simple and good identification method, that is, put it on a piece of wired paper and put it upside down to see if you can see the line through it. If you can, it is imitation diamond, and natural diamonds are invisible.

Observation with a magnifying glass: Because the hardness of diamond is very high, it reaches 10 hardness. So we can observe the waist of the diamond. If the waist is frosted, this method is the most suitable. Because diamond is harder than any imitation, there will be no fine lines like imitation, and the waist of diamond is granular. Similarly, because diamonds are harder than imitations, the faceted edges of imitations are often duller than diamonds, and the faceted edges of diamonds must be sharp.

There is also the simplest way. Purchase is judged by certificates, especially authoritative international certificates (such as GIA and IGI). ). Because the GIA certificate corresponds to a unique diamond, the code of the diamond is also unique, just like a person's ID number. Just use a magnifying glass to find the string of codes at the waist of the diamond and check the certificate code.