Vincent told Qin Shiou helplessly that technology is developing more and more and more methods of fraud are being made, which makes it much more difficult for jewelers to identify black pearls.

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

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

Then he put the silver-white pearl in an airtight container and shines 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 reduce chemicals in the coating under strong light, making the silver-white coating black. Of course, this is just a demonstration. In fact, the steps are more cumbersome, the time it takes is longer, and the black pearls produced are also more realistic."

Qin Shiou raised his thumbs up and said, "Human wisdom is really endless. It can be created with such technical content even if it is fake. The 21st century is indeed the era of science. I have to go to university to study."

"How to fake learning?" Vincent teased.

Qin Shiou laughed. In fact, he felt a little guilty because his black pearls were also a bit fake. There is also a common method of fraud that is dyeing the bead core. After dyeing the bead core black, it is implanted into the pearl shells. During the pearl formation process, the melanin preparation is constantly added to the pearl shells, and the final pearl is pure black.

He used to have been growing too slowly, so he put small pearls in Black Butterfly Berry, and the black butterfly Berry secreted substances to surround them.

The experts Vincent asked Qin Shiou to demonstrate two other methods of fraud. One is to place the pearl under the gamma ray of cobalt source to make black, which is the ray radiation method. The last one is to apply a thin film surface, applying a very thin layer of black gel on the surface of the pearl...

While Qin Shiou was watching these demonstrations, one hundred and twenty-eight black pearls were assigned to different experts and they began to distinguish them.

It still starts with physical identification. First look at the color. This time I used an instrument similar to a microscope. It has a bracket that can accommodate a circle of eight black pearls at a time. After putting the black pearls on it, the bracket lifts the black pearls, and then several rays of light will scatter from all around on the black pearls.

Vincent explained: "There are no two identical leaves in the world, nor two identical black pearls. Natural black pearls have different colors from light gray to black, and their beauty lies in the colour of the tone of the expression. Under astigmatism, the black pearls slowly turn. You can see a slight flash of change, just like a rainbow."

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

Vincent laughed and said, "Of course, you can't see it, because that must be viewed in a tenfold mirror."

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 all have some unusual shapes, such as pear-shaped, water drop-shaped, dumbbell-shaped, etc. The black pearls brought by Qin Shiou are almost all perfectly round, so this is so valuable. One piece costs tens of thousands or hundreds of thousands of dollars.

Speaking of this, Vincent teased again, saying that the black pearls he provided for the first time to make the Dark Night Queen were so outstanding in shape. He subconsciously thought that they were all breeding black pearls, so he did not come to see Qin Shiou at the beginning, otherwise he would have to entertain such potential customers no matter what.

Qin Shiou smiled and said, "Maybe they are really breeding pearls, because they are all grown from my fishing ground."

Vincent also laughed, and then asked in a seemingly casual tone: "For so many high-quality black pearls, I'm afraid Tahiti's annual output is not the same. Qin. How did you get it? Don't tell me that 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 Tahitian black pearls is one in 10,000. That is to say, only one out of 10,000 black butterfly shells can brew black pearls! And the black pearls produced in this way may be of irregular shape or poor color, so 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 big. One imitation pearl only costs a few dollars. A breeding pearl only costs tens of hundreds of dollars, and wild pearls usually cost thousands of dollars, while the price of top-quality natural pearls is definitely costing tens of thousands or more than tens of thousands of dollars.

The most important thing in physical testing is machine testing. Although the eyes and feelings of treasure appraisal experts are very powerful, people may misstep and there is always a possibility of seeing things. Of course, precision machines are not completely reliable, but the final result of experts' eyes and precision machines' judgments is very reliable.

So, Vincent later introduced a series of black pearl identification techniques to Qin Shiou, mainly four, each targeting the same counterfeiting technology.

First, the ultraviolet fluorescence test is used, which is for film coating technology. A light-emitting machine emits ultraviolet light on the black pearl. Under ultraviolet light, the black pearls often fluorescent, and the color changes from bright red to coffee red, which is extremely gorgeous. The film-coated pearls have a layer of black gel on the outside, so they mostly do not respond to ultraviolet light.

The second is X-ray photography detection. Vincent said that this technology is specifically used to determine whether cultured pearls have been dyed with silver salt. After shooting black pearls with x-ray, the videos illuminated by the machine can distinguish the dyed pearls treated with silver salt. There is a circle of light white between the pearly substance and the nucleus of this pearl.

The third method is called x-ray fluorescence testing, which also uses an x-ray machine, but is not taking photos but emitting light. All jades can emit radiation at a specific wavelength under x-ray irradiation. Using the spectral measurement of the wavelength, we can distinguish whether this is a pure black pearl or a cultured pearl made of ray radiation.

The last one is infrared photography testing. This is aimed at breeding pearls made from dyed bead nucleus technology. The infrared ray has extremely strong penetration and can penetrate the pearl nucleus. If it is a breeding pearl, the angle will change due to the uneven texture and the infrared ray penetrates the black pearl and shoots it out.

This is the one that Qin Shiou is most worried about, because some of the black pearls here use other types of pearls as pearl cores! (To be continued.)
Chapter completed!