Chapter 1666

Vincent reluctantly introduced to Qin Shiou that now the development of science and technology is more and more advanced, and there are more and more means of counterfeiting, which makes it difficult for jewelers to identify black pearls.

At present, there are four main methods to cultivate black pearls: silver salt treatment, ray radiation, dyeing pearl core and film coating.

The first one is the most used. Vincent called a staff member in a white coat to demonstrate to Qin Shiou. This method is to soak the Pearl in several reagents. After soaking for a while, the staff took it out and said, "this is silver nitrate and dilute amonia solution, which can cover the surface of the Pearl with a silver coating."

Then he put the silver pearl into a closed container and irradiated it with strong light. In this way, the color of the Black Pearl changed from white to black.

"There is hydrogen sulfide in it, which can react with the chemicals in the coating under strong light to turn the silver white coating into black. Of course, this is just a demonstration. In fact, the steps are more cumbersome, the time is longer, and the black pearls are more realistic. "

Qin Shiou thumbed up and said, "human wisdom is really infinite. Counterfeiting can also be made with such technical content. The 21st century is indeed an era of science. I have to go to university for further study."

"Learn how to fake?" Vincent joked.

Qin Shiou laughs. In fact, he is a little guilty, because his black pearls are also a little fake. Another common way of fake is Pearl core dyeing. After the Pearl core is dyed black, it is implanted into pearl shell. Melanin preparation is continuously added to pearl shell in the process of pearl formation. Finally, the pearl is pure black.

He used to put small pearls in the black butterfly shell because the pearls grew too slowly. The Black Pearl came out when the black butterfly shell secreted substances to surround them.

Vincent's expert showed Qin Shiou two other counterfeiting methods. One is to irradiate the Pearl into black under the gamma ray of cobalt source, which is the radiation method. The last one is film coating. Apply a thin layer of black gum on the surface of the Pearl

When Qin Shiou watched these demonstrations, 128 black pearls were assigned to different experts, and they began to distinguish.

We still start with physical discrimination and look at the color first. This time, we use an instrument similar to a microscope. It has a bracket that can hold eight black pearls at a time. After putting the black pearl on it, the bracket will hold the Black Pearl up, and then several rays of light will scatter on the black pearl from all around.

Vincent explained, "there are no two identical leaves and no two identical black pearls in the world. Natural black pearls have different colors from light gray to black, and its beauty lies in the color matching on the look tone. Under the astigmatism, rotate the Black Pearl slowly, and you can see a slight flash changing constantly, just like a rainbow. "

Qin Shiou stared at the black pearls carefully, then shook his head awkwardly and said, "it seems that this needs professional vision, I can't see it."

Vincent laughed and said, "of course, you can't see it, because it has to be viewed with a tenfold mirror."

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

Vincent said that few wild black pearls can produce particularly round types. Almost all of them have some special shapes, such as pear shape, water drop shape, dumbbell shape and so on. The black pearls brought by Qin Shiou are almost perfectly round, so they are so valuable. Each one costs tens of thousands of dollars.

Speaking of this, Vincent joked again. He said that he saw for the first time that the black pearls he provided to make the dark night queen were so excellent in shape. He subconsciously thought they were all cultured black pearls, so he didn't come to see Qin Shiou at the beginning. Otherwise, he had to entertain such potential customers no matter how.

Qin Shiou said with a smile, "maybe they are really cultured pearls, because they are cultured in my fishing ground."

Vincent also smiled, and then asked in a seemingly casual tone, "I'm afraid Tahiti's annual output of so many high-quality black pearls is only so, Qin, how did you get it? Don't tell me, your fishing ground has more black butterfly shells than Tahiti. "

Not all black butterfly shells can produce black pearls. According to probability statistics, the probability of producing black pearls in Tahiti is one in 10000, that is, only one of 10000 Black Butterfly shells can brew black pearls! The black pearls produced in this way are uncertain. They may be irregular in shape or poor in color. Therefore, few high-quality black pearls can be produced every year.

This is also the reason why there is such a big price difference. Imitation pearls only cost a few dollars, cultured pearls only cost tens of thousands of dollars, wild pearls usually cost thousands of dollars, and the price of best natural pearls must be tens of thousands or hundreds of thousands of dollars.

The most important thing in physical testing is machine testing. Although treasure forensics experts have strong eyes and feelings, people may miss a hand and a horse may miss a foot, and there is always the possibility of losing their eyes. Of course, precision machines are not completely reliable, but with the eyes of experts and the judgment of precision machines, the final result is very reliable.

So, later Vincent introduced a series of Black Pearl identification techniques to Qin Shiou, including four kinds, each aiming at the same counterfeiting technology.

The first is the UV fluorescence test, which is aimed at the thin film coating technology. The ultraviolet light emitted by the light emitting machine is on the black pearl. Under the irradiation of ultraviolet light, the Black Pearl often has fluorescence, and the color changes from bright red to coffee red, which is extremely gorgeous. Thin film coated pearls have no reaction to ultraviolet light because they have a layer of black colloid on the surface.

The second is X-ray photo detection. Vincent said that this technology is specially used to judge whether cultured pearls have been dyed with silver salt. After the black pearls are photographed with X-ray, the film irradiated by the machine can distinguish the dyed pearls treated with silver salt. There is a circle of light white between the Pearl substance and the Pearl core.

The third method is called X-ray fluorescence test, which also uses an X-ray machine, but not taking pictures, but emitting light. All jade can emit radiation of specific wavelength under X-ray irradiation. By measuring the degree of wavelength with a spectrometer, you can distinguish whether it is a pure black pearl or a cultured pearl made of radiation.

The last one is infrared photography test, which is aimed at cultured pearls produced by dyeing pearl core technology. The infrared penetration is very strong and can penetrate into Pearl core. If it is cultured pearls, because the texture is uneven, the angle will change after the infrared ray penetrates into the black pearl and then shoots out.

This is the one that Qin Shiou is most worried about, because some of his black pearls here use other kinds of pearls as pearl cores!