Vincent was helpless to introduce to Qin Shiou, saying that now that the development of science and technology is more and more advanced, and there are more and more counterfeiting methods, it is much more difficult for jewelers to identify black pearls.

  There are currently four main methods for cultivating black pearls: silver salt treatment, radiation, dyed bead nucleus, and film coating.

The most used is the first one. Vincent called a staff member in a white coat to show Qin Shiou. This method is to soak the pearls in several reagents. After soaking for a while, the staff will He took it out and said, "This is a solution of silver nitrate and dilute Amonia, which can make the pearl surface covered with a silver coating."

   Then he put the silver-white pearl into an airtight container and irradiated it with strong light, so slowly, the color of the black pearl changed from white to black.

"There is hydrogen sulfide in it, which can react with the chemical substances in the coating under strong light, so that the silver-white coating becomes black. Of course, this is just a demonstration. In fact, the steps are more cumbersome and time-consuming. Longer, the black pearls produced are more realistic."

  Qin Shiou gave a thumbs up and said: "Human wisdom is really infinite, and fraud can be made with such a technical content. The 21st century is indeed the age of science. I have to go to university for further study."

  "Learn how to fake it?" Vincent teased.

Qin Shiou chuckled. In fact, he was frustrated, because his black pearls were also a bit fake. Another common method of fraud is to dye the pearl nucleus. After the pearl nucleus is dyed black, it is implanted in the pearl oyster, and the pearl oyster is continuously transferred to the pearl oyster during the formation of the pearl. The melanin preparation is added, and the final pearl is pure black.

  He used to grow too slowly because of pearls. Small pearls are placed in the black butterfly shell, the black pearls that come out after the black butterfly shell secretes them to surround them.

  Vincent’s experts also showed Qin Shiou two other methods of forgery. One is to irradiate the pearl under gamma rays from a cobalt source to make it black. This is the ray radiation method. The last one is film coating. Apply a thin layer of black glue on the surface of the pearl...

  When Qin Shiou watched these demonstrations, one hundred and twenty-eight black pearls were assigned to the hands of different experts, and they began to distinguish.

   still starts from physical identification, first look at the color. This time I used a microscope-like instrument, which has a bracket that can hold a circle of eight black pearls at a time. After putting the black pearl on, the bracket will hold the black pearl, and then there will be a few rays of light scattered on the black pearl from all around.

Vincent explained: "There are no two identical leaves or two identical black pearls in the world. Natural black pearls have different colors from light gray to black, and its beauty lies in the basic tone of the look. Accompanying color. Under astigmatism, slowly turn the black pearl. You can see a slight flash of light constantly changing, just like a rainbow."

  Qin Shiou stared at the black pearls carefully, then shook his head awkwardly, “It seems that this requires a professional perspective, I can’t see it.”

  Vincent laughed and said: "Of course, of course you can't see it, because that would have to be viewed with a tenfold lens."

  This microscope not only observes the color of the black pearl, but also measures its roundness, diameter, brightness and other parameters.

  Vincent said that wild black pearls rarely produce particularly round types. Almost there are some abnormal shapes, such as pear shape, drop shape, dumbbell shape and so on. The black pearls Qin Shiou brought here were almost perfectly round, so they were so valuable, each costing tens of thousands and hundreds of thousands of dollars.

Speaking of this, Vincent laughed again, saying that the first time he saw the black pearls that he provided to make the Queen of the Night was so good, he subconsciously thought that they were all cultured black pearls, so he didn't come to see Qin Shiou at the beginning, otherwise Such potential customers, he has to entertain him no matter what.

  Qin Shiou smiled and said, "Perhaps they are really cultured pearls, because they are all cultivated in my fishery."

  Vincent also laughed. Then he asked in a seemingly casual tone: "So many high-quality black pearls. I am afraid that Tahiti's annual output is not enough. Qin, how did you get it? Don't tell me, your fishery is better than Tahiti. More black butterfly shells."

  Not all black butterfly shells can produce black pearls. According to probability statistics, the probability of producing Tahitian black pearls is 1 in 10,000. In other words, only one of 10,000 black butterfly shells can brew black pearls! And the black pearls produced in this way are uncertain. They may be irregular in shape or poor in color. Therefore, there are very few high-quality black pearls that can be produced every year.

This is also the reason why the price difference is so large. An imitation pearl only costs a few dollars, a cultured pearl only costs a few hundreds of dollars, a wild pearl usually costs several thousand dollars, and the price of a premium natural pearl is definitely tens of thousands of dollars. Hundreds of thousands of dollars.

  The most important thing for physical testing is machine testing. Although Jianbao experts have great eyes and feelings, people may miss their hands and horses, and there is always the possibility of missed eyes. Of course, precision machinery is not completely reliable, but the eyes of experts and the judgment of precision machinery will make the final result very reliable.

  So, Vincent later introduced a series of black pearl identification techniques to Qin Shiou, there are mainly four kinds, each of which is aimed at the same counterfeit technique.

  First is the ultraviolet fluorescence test, this is for the thin film coating technology. The ultraviolet light is projected on the black pearl with a radiometer. Under ultraviolet light, the black pearl often has fluorescence, and the color changes from bright red to coffee red, which is extremely gorgeous. Film-coated pearls do not respond to ultraviolet light because they have a layer of black gum on the outside.

The second is X-ray photo detection. Vincent said that this technology is used to determine whether cultured pearls have been dyed with silver salt. After taking black pearls with X-rays, the film irradiated by the machine can be dyed with silver salt. The pearl distinguishes it, and there is a circle of light white between the nacre and the nucleus of this pearl.

  The third method is called X-ray fluorescence test, which also uses X-ray machine, but instead of taking photos, it is shooting light. All jade stones can emit radiation of a specific wavelength under X-ray irradiation. By measuring the degree of wavelength with a spectrometer, it can be distinguished whether it is a pure black pearl or a cultured pearl made of radiation.

  The last one is infrared photography test. This is aimed at cultured pearls produced by dyed bead nucleus technology. Infrared rays have strong penetrating power and can penetrate into the pearl nucleus. If it is a cultured pearl, because of the uneven texture, the angle will change after the infrared rays penetrate into the black pearl and then shoot out.

  This is the one that Qin Shiou is most worried about, because some of his black pearls here use other types of pearls as pearl nuclei! (To be continued~^~)