Chapter 55 Who says you can't use radiation testing to identify antiques?

Evidence Room.

The long table was arranged in a circle, with five professors and their assistants each occupying a corner.

As Zheng Jian looked closely, a commotion came from outside the door: Guan Xingmin pushed Lin Sicheng through the door.

Wang Qizhi followed closely behind, watching the spectacle with amusement.

They even argued as they walked:

"Director Guan, are you making things difficult for people by detecting radiation with the naked eye?"

"If I don't make things difficult for you, the boss will make things difficult for me. Besides, it wasn't said that you couldn't use the equipment."

"What's the difference between my test and others' tests?"

“It’s different anyway!” Guan Xingmin lowered his voice. “Since you’re already here, lend a hand: even if you just go through the motions!”

After some pushing and shoving, they finally pushed him to the edge of the long table, where Lin Sicheng hesitated.

It's estimated that the leader just mentioned it casually, but Guan Xingmin, being an expert, actually carried it out meticulously.

It's no exaggeration to say that if word got out, it would make those in the know laugh their heads off.

He gave a thumbs-up with a sigh: "Director Guan, your execution is truly impressive!"

"Nonsense, otherwise how could I be the director?"

Lin Sicheng sighed, then looked at Wang Qizhi, who smiled and nodded.

The higher-ups just talk, while the people below run themselves ragged... Why don't you try running one yourself?

Just like Guan Xingmin said: even if it's just going through the motions.

Lin Sicheng had no choice but to put on gloves and pick up the handheld radiation detector.

Its scientific name is Geiger counter, and it can detect alpha, beta, gamma, and X-rays. It's extremely easy to operate: simply turn it on, and a small screen will display numbers. If the radiation exceeds the safe limit, an alarm will sound and a red light will flash.

Then, like a fool, Lin Sicheng took a handheld game console and kept shining it at the artifacts on the long table.

The head of the physical evidence department and a policewoman stood on either side of each other, holding folders and taking meticulous notes.

Is this setup formal or not?

The teaching assistants secretly scoffed: What's the point of measuring radiation levels on an antique? Isn't this just a case of someone trying to get credit for something they don't actually have?

It's not tested much, mainly because it's not very useful.

Shaking their heads and sighing, the professors went about their respective duties.

It was indeed quite simple. Since he had nothing better to do, Wang Qizhi asked again, "How did that reverse-flow pot manage to fool carbon-14 and thermoluminescence dating instruments?"

"Utilize the radiative decay characteristics of atomic isotopes!"

Wang Qizhi nodded: "I understand the principle, but I'm asking how antique dealers manage to deceive everyone?"

Lin Sicheng shook his head: "I don't know!"

Wang Qizhi was skeptical: "You don't know?"

You don't know, you dared to pick up a stool and smash it, sending two "Hong Kong businessmen" to the hospital?

Lin Sicheng did know, but he couldn't say because the technology was too advanced, especially thermoluminescence.

To put it simply: the crystals such as quartz, feldspar, and calcite in kaolin clay have the property of absorbing radiation energy, but when the temperature reaches above 800 degrees Celsius, all the radiation energy will be released.

After firing in a kiln, all the radiation energy in the porcelain is reset to zero, and then the mineral crystals absorb it at a constant rate. The longer the firing time, the more radiation is absorbed.

Thermoluminescence utilizes this property: a sample is heated at around 500 degrees Celsius, causing the crystal to slowly release energy. The total energy of the radiation is then measured to calculate the firing date of the porcelain.

The fake was just burned, so it naturally doesn't contain any radiation energy. How could it fool the instruments?

Adding a small amount of a mineral element that is in the process of decaying, such as depleted uranium, will solve the problem. The more you add, the older the age will appear to the instrument.

However, there is a high technical barrier to entry, and not many people in China understand it, and almost no one does it.

Therefore, Lin Sicheng suspected that the reverse-flow pot was most likely a product of some foreign laboratory.

It's not surprising; there will only be more and more of these things in the future: around 2015 or 2016, shiploads of Tang tri-color pottery and Yuan blue-and-white porcelain will be brought in...

Wang Qizhi didn't ask any further questions, and Lin Sicheng went through the motions methodically.

"A Kangxi period (1620-1625) imitation of a Yongle period (1620-1625) 'Foreigners' music and dance' vase, with a radiation level of 0.09 micrograms..."

"Ming Dynasty Zhou Wenjing's 'Ancient Forest and Crows' painting, 0.005... Never mind, ignore it..."

"A Qing Dynasty Xianfeng period plum blossom snow-themed glass bowl, 0.12 micrometers..."

After testing about twenty items, Lin Sicheng was losing patience. Seeing that the professors had already appraised most of them, he rolled his eyes...

"Director Guan, how about we do the test this afternoon?"

By the afternoon, Lin Sicheng would have already run away?

"Check a few more items, check a few more items..." Guan Xingmin coaxed a child, "Tonight at Tang Le Palace, aren't you going to thank Professor Wang?"

Lin Sicheng was stunned: After all this time, I still have to pay?

Fine, I'll help them all the way.

Lin Sicheng continued: "A Song Dynasty Cizhou white-ground black-flower brush washer, 0.14 micrometers..."

"Yuan Dynasty Hetian jade white lion paperweight, 0.001, negligible..."

"Liao-Jin Dynasty Blue Glass Openwork Incense Burner, 0.17 micrometers..."

"A box of Yuanfeng Tongbao coins from the Northern Song Dynasty, Emperor Shenzong... negligible...wait, is the machine broken?"

They had already walked past when Lin Sicheng exclaimed "Eh!"

Guan Xingmin and Wang Qizhi thought there was something wrong with the box of copper coins. But then they checked the radiation meter: 0.001... which was indeed negligible.

Furthermore, this is a copper coin, not a mineral crystal, and it's covered in rust, so it's not normal for its radiation level to be low.

What's wrong with that?

Just as he was completely confused, Lin Sicheng turned back:

Liao-Jin Dynasty Blue Glass Openwork Incense Burner, 0.17...

Yuan Dynasty Hetian jade white lion paperweight, 0.001...

Song Dynasty Cizhou white-ground black-decorated brush washer, 0.14...

Lin Sicheng looked at the screen of the radiation meter and exclaimed "Ha!"

What did I just say?

Mineral crystals absorb radiation energy at a constant rate. Not to mention the past, from the Yuan Dynasty to the present, seven or eight hundred years ago, where did the radiation energy absorbed by this piece of jade go?

The two followed: "What's wrong?"

"Hetian jade, 0.001?"

Still a little drunk, Wang Qizhi was still pondering what the connection was between Hetian jade and 0.01 when Guan Xingmin's eyes widened.

Even ancient paintings from the Ming Dynasty have a value of 0.005, while jade lions from the Yuan Dynasty have a value of 0.001?

The former is merely paper, processed after the fact, while the latter is jade, naturally sculpted. But is the radiation from a paper painting five times that of jade?

This is even more ridiculous than asking Lin Sicheng to identify a radiation source with the naked eye...

Just as he found it utterly absurd, Lin Sicheng took the folder from the policewoman:

Item: Jade White Lion Paperweight.

Era: Yuan.

Material: Hetian jade.

Excavation site: Yuan Dynasty tomb in Hengshan County, YL City (pending review).

Forensic institutions: Provincial Department of Justice Forensic Center, Municipal Bureau of Justice Forensic Center...

Expert panel members: ...

Continue flipping down to the second page:

The review unit was the guidance group of the School of Cultural Heritage of Northwest University.

Re-examination expert: Yu Zijian.

The last line was suddenly signed by Professor Yu.

Lin Sicheng frowned.

There's no doubt that this jade lion is fake. The problem is that neither the provincial nor the municipal bureau has been able to authenticate it.

The key point is that even Professor Yu, an expert in stone carvings and jade artifacts at the academy, couldn't identify it.

What do we do now?

Wang Qizhi realized what was happening and his eyes widened: Who said that you can't use radiation measurement to identify antiques?

That's how it was identified, isn't it?

With such low radiation levels, there's no doubt that this jade lion is definitely problematic.

The problem is, what about Professor Yu's signature and this appraisal report?

Just as he was thinking of an idea, Lin Sicheng blinked: "It's not stamped yet!"

Of course, the stamp is still in my bag.

Still wondering what this kid meant, Lin Sicheng silently opened the clasp and pulled out the second report, which was Professor Yu's re-examination report.

With Wang Qizhi, Guan Xingmin, the section chief, and the policewoman present—eight eyes in total—Lin Sicheng calmly stuffed the paper into his pants pocket.