Chapter 55: Who Says You Can't Use Radiation Detection to Authenticate Antiques?

Evidence room.

Long tables were arranged in a circle, with five professors and their assistants each occupying a corner.

Just as they were carefully appraising the items, a commotion arose outside the door: Guan Xingmin pushed Lin Sicheng into the room.

Wang Qi Zhi followed closely behind, looking as if he were there to watch the fun.

They were arguing as they walked:

"Section Chief Guan, using the naked eye to detect radiation? Aren't you making things difficult for me?"

"I'm not making things difficult for you; the leadership is making things difficult for me. Besides, nobody said you couldn't use instruments, did they?"

"Then what's the difference between me measuring it and someone else doing it?"

"It's different, regardless!" Guan Xingmin lowered his voice. "Since you're already here, just do me a favor: even if you're just going through the motions!"

After some pushing and shoving, they were forced to the side of the long table, and Lin Sicheng was exceptionally hesitant.

He reckoned the leadership had at most just mentioned it in passing, yet Guan Xingmin, who was supposedly an expert, was actually executing it with such meticulousness?

It was no exaggeration; if word got out, it would really make those in the know laugh their heads off.

He helplessly gave a thumbs-up: "Section Chief Guan, your execution is top-notch!"

"Nonsense, why else would I be a Section Chief?"

Lin Sicheng sighed and looked at Wang Qi Zhi, who smiled and nodded.

The higher-ups just wag their tongues, while the subordinates run their legs off... why don't you try not running?

Just as Guan Xingmin said: even if it was 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 a Geiger counter, capable of detecting alpha, beta, gamma, and X-rays. The operation is extremely simple: turn on the switch, and the small screen displays the numbers. If the radiation exceeds the safety limit, it will sound an alarm and flash a red light.

Then, Lin Sicheng acted like a fool, holding the handheld device and continuously scanning the Cultural Relics on the long table.

The Section Chief of the Evidence Division and a policewoman stood on his left and right, holding a Folder and recording everything very carefully.

Just ask yourself, with this setup, isn't it formal enough?

The assistants secretly curled their lips: why measure radiation values on antiques? Isn't this just making up the numbers to get credit?

It is indeed rarely measured, and the key is that it's of little use.

Shaking their heads and sighing, the several professors each attended to their own duties.

It was indeed quite simple, and since they were idle anyway, Wang Qi Zhi asked again: "That Inverted Pot, how did it fool dating instruments like Carbon-14 and Thermoluminescence?"

"By utilizing the radioactive decay properties of atomic isotopes!"

Wang Qi Zhi nodded: "I understand the principle, but I'm asking how the antique traffickers pulled the wool over everyone's eyes?"

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

Wang Qi Zhi was half-doubting: "You don't know?"

If you didn't know, would you dare to pick up a stool and smash it, putting two "Hong Kong merchants" in the hospital?

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

To put it simply: crystals in porcelain clay such as Quartz, Feldspar, and Calcite all have the property of absorbing radiation energy from radioactive elements (uranium, thorium, potassium-40) in the soil, but when the temperature reaches above 800 degrees, all radiation energy is released.

It is equivalent to saying that after being fired in a kiln, all the energy in the porcelain resets to zero, and then the mineral crystals absorb it again at a constant rate. The longer the time, the more it absorbs.

Thermoluminescence utilizes this property: samples are heated, with the temperature controlled at around 500 degrees, causing the crystals to slowly release energy, then the total intensity of the light is measured to calculate the firing era of the porcelain.

Forgeries are freshly fired, so naturally, they contain no radiation energy, so how do they fool the instruments?

There are two methods. The first is very simple, and Wang Qi Zhi and Guan Xingmin know it too: pass the item through a machine with ray-emitting functions dozens or hundreds of times. For example, airport security scanners, hospital X-ray Machines, CT scans, or even Gamma ray machines and γ afterloading therapy machines.

But there is a drawback: direct irradiation by rays will cause the Glaze Layer to become cloudy or even fade.

Imagine a glass bottle left out in the sun for several years... you wouldn't even need to do any testing; the naked eye could tell the difference, so it is rarely used.

The second method is like the Inverted Pot: add a little mineral element currently in its decay period, such as Depleted Uranium. The more you add, the older the age calculated by the instrument. Not only is the effect obvious, but it is also long-lasting... for hundreds of millions of years!

But there is a technical threshold, and it is very high; few people in the country understand it, and almost no one does it.

Therefore, Lin Sicheng suspected that the Inverted Pot was, in all likelihood, the product of some laboratory abroad.

It's not surprising; things like this will only become more common in the future: by about 2015 or 2016, Tang Sancai and Yuan blue-and-white porcelain will be brought in by the boatload...

Wang Qi Zhi did not pursue the matter further, and Lin Sicheng went through the motions in an orderly manner.

"Qing Kangxi Imitation Ming Yongle 'Hu People's Music and Dance' horse-hanging vase, radiation value 28 micro..."

"Ming Zhou Wenjing's 'Ancient Forest and Cold Crows', 08... never mind, negligible..."

"Qing Xianfeng Chunmei reporting snow glazed Bowl, 76 micro..."

After measuring about twenty items, Lin Sicheng lost his patience. Seeing that the professors had appraised most of them, he rolled his eyes:

"Section Chief Guan, how about we continue the inspection this afternoon?"

If he waited until the afternoon, wouldn't Lin Sicheng have already run off?

"Just a few more, just a few more..." Guan Xingmin coaxed him like a child. "Tonight at Tang Le Gong, aren't you going to thank Professor Wang?"

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

Forget it, might as well help to the end.

Lin Sicheng continued: "Song Cizhou white-ground black-flower Brush Washer, 42 micro..."

"Yuan Dynasty Hetian Jade white lion Paperweight, 02, negligible..."

"Liao-Jin blue glazed hollow incense burner, 86 micro..."

"Northern Song Shenzong Yuanfeng Tongbao, one box... negligible... hey, wait, is the machine broken?"

Having already walked past, Lin Sicheng let out an "Eh?".

Guan Xingmin and Wang Qi Zhi thought there was something wrong with that box of copper coins. But looking at the radiation detector again: 02... it was indeed negligible.

Furthermore, these were copper coins, not mineral crystals, and they were covered in rust; wasn't it normal for the radiation value to be low?

Where is the mistake?

While completely bewildered, Lin Sicheng scrolled back:

Liao-Jin blue glazed hollow incense burner, 86...

Yuan Dynasty Hetian Jade White Lion Paperweight, 02...

Song Cizhou white-ground black-flower brush washer, 42...

Lin Sicheng looked at the radiation detector screen and let out a "Ha."

What was just said?

Mineral crystals absorb radiation energy at a constant rate; setting that aside, from the Yuan Dynasty until now, seven or eight hundred years, where did the radiation energy this jade absorbed go?

The two followed him over: "What is it?"

"Hetian Jade, 02?"

Still a bit tipsy, Wang Qi Zhi was still pondering what connection Hetian Jade had with 02, when Guan Xingmin's eyes bulged.

Even an Ancient Painting from the Ming Dynasty has 08, yet the Yuan Dynasty Jade Lion Paperweight is only 02?

The former is just paper, processed later, while the latter is jade, naturally carved. Yet the radiation level of the paper painting is four times that of the jade?

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

Just as he felt it was incredibly absurd, Lin Sicheng took the Folder from the female police officer's hand:

Item: White Jade Lion Paperweight.

Era: Yuan.

Material: Hetian Jade.

Excavation Site: YL City Hengshan County Yuan Dynasty ancient tomb (pending review).

Appraisal Unit: Provincial Department Appraisal Center, Municipal Appraisal Center...

Appraisal Members:...

Continuing to flip down, second page:

Re-appraisal Unit: Xida Cultural Heritage College Guidance Group.

Re-appraisal Expert: Yu Zijian.

On the last line, the Daimyo of Professor Yu was signed abruptly.

Lin Sicheng frowned.

This Jade Lion Paperweight is definitely fake, that is beyond doubt. The problem is, the Provincial Department and Municipal Bureau didn't identify it.

The key is: the college's stone carving and Jade Expert Professor Yu didn't identify it either.

What to do now?

Wang Qi Zhi reacted, his eyes wide: Who said you can't use radiation value measurement to identify antiques?

Didn't this just identify it?

The radiation value is so small, there is no need to doubt: this Jade Lion Paperweight definitely has a problem.

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 hasn't been stamped yet!"

Nonsense, the stamp is still in my bag?

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

With Wang Qi Zhi, Guan Xingmin, the Section Chief, and the female police officer, four people with eight eyes, it could be called being under the gaze of the public. With an incredibly calm posture, Lin Sicheng stuffed that piece of paper into his pants pocket.