Restoring cultural relics: Starting with the crying Tang Dynasty figurines

Su Yuan did not agree immediately, but placed the knife-shaped coin on the bedside table and carefully examined it against the light from the window on the left.

The corrosion of bronze is a long process, and this Ming dynasty knife is covered with multiple layers of corrosion.

The bottom layer is red rust of cuprous oxide, the middle layer is green rust of basic copper carbonate, and the top layer is grayish-white rust of lead oxide. Several layers of rust are interwoven together!

The most critical issue is that in the middle section of the blade, there is a mineralized spot that has been punctured, and the surrounding metal matrix has completely lost its ductility.

The powder falls off with a light touch of your finger.

As Su Yuan touched the knife-shaped coin, he had a feeling that he was very familiar with. It was an indescribable "aura" that every ancient artifact possessed!

After reading it, Su Yuan turned around and said to Zhao:

"Keep the item here, I'll give it a try. But I don't know how long it will take. Please leave your contact information, and I'll send it to you when it's fixed."

Zhao thanked Su Yuan profusely, left his contact information, and departed.

Without delay, he took the first step: cleaning. Su Yuan covered the bedside table with a tablecloth to prevent damage to the guesthouse's property.

The cleaning of rust on all bronze artifacts from the Warring States period required the utmost care and precision.

Soluble harmful rust must be removed, but stable rust cannot be moved, as it has become integrated with the body; forcibly removing it would destroy the original characteristics of the artifact!

Su Yuan used a mechanical cleaning method, without using any chemical reagents.

Using only sharpened bamboo skewers and soft brushes, the surface dirt was peeled off bit by bit under a magnifying glass, at a speed as slow as a snail's pace.

It wasn't until 10 p.m. that he cleaned less than two centimeters of the handle of the knife coin.

I've replaced several bamboo skewers, and I only replaced them when they were completely dull, because I was afraid that the new bamboo skewers would be too sharp and scratch the rusty surface!

Miao Deyu, watching from the bronze mirror, was anxious and muttered, "At this rate, you won't finish repairing it by the New Year."

Su Yuan smiled and ignored it, putting away the knife coins first, and continuing to repair them when he returned to the unit.

After tidying up the bedside table, I took a shower and went to bed...

After returning to the unit, I hurriedly ate something and, without even saying hello to them, rushed into the warehouse!

He ran into trouble today while cleaning the middle section of the blade.

The mineralization was more severe than he had anticipated!

The surrounding metal had completely lost its strength; the bamboo skewer crumbled at the slightest touch, like a broken biscuit.

Su Yuan dipped a brush in distilled water and touched the rusty surface a short distance away, intending to test the water absorption rate of the rust layer.

As a result, the water droplets were absorbed as soon as they touched the rusty surface, spreading three times faster than normal bronze artifacts!

This indicates that numerous capillary channels have formed inside the rust layer, making the entire structure loose. This also stirred a sense of impatience in Su Yuan's heart.

Su Yuan put down his brush, took a deep breath, and stood up, pacing back and forth in the warehouse several times.

Then he started rummaging through things, not in the toolbox, but among the pile of old objects on the shelf against the wall.

Zhong Ming once said that his great-grandfather, Su Demao, repaired a batch of Warring States period bronzes in Yi County using a reinforcement method that no one remembers now!

After flipping through the pages for almost an hour, Su Yuan finally found a notebook. The words on the cover were blurred, and the paper inside was very fragile.

He carefully turned the book and found a passage of text near the back, the ink having faded to brown:

"In the third month of the year Yihai, a set of bronze knife coins was unearthed in Yi County, Yanxiadu. The coins were heavily corroded and the body was mineralized."

"The conventional method is not applicable. Shellac must be dissolved in alcohol and diluted to the consistency of water. Then, use a very fine brush to apply it to the rusted surface and allow it to penetrate naturally."

"Too much glue will block the spiritual orifices, too little will not be firm. Repeat this three times, and wait for the glue to dry completely before the embryo solidifies on its own."

Su Yuan memorized the text, put the notebook back in its place, and began to work on it!

He has shellac on hand; it's an old-fashioned purple shellac sheet that needs to be soaked in alcohol to dissolve.

Following the proportions in his notes, he diluted the shellac solution to a transparent consistency, then used the finest wolf-hair brush to gently apply a layer to the mineralized areas of the knife-shaped coin.

The alcohol evaporated quickly, and the shellac dried out in fifteen minutes.

Su Yuan then gently poked at the treated area with a bamboo skewer. The powder no longer fell off, but the structure was still relatively loose, so a second application was needed!

After the second coat was applied, it penetrated even deeper.

On the third attempt, Su Yuan only touched up the most severely affected small area and then stopped.

He remembered very clearly a sentence Zhong Ming once said:

"When your great-grandfather's generation repaired things, they believed in stopping when they had enough. Any more than that would be a waste."

Once the shellac has completely solidified, the mineralized area changes from a powdery state to a porous structure with a certain strength, which can stably maintain its shape, although the color becomes a bit darker!

Su Yuan dipped a brush in a diluted B72 solution, mixed it with a trace of mineral pigment, and applied a light layer of color coordination to the reinforced area.

This isn't a cover-up; it's just to make the contrast between the repaired area and the surrounding rust less jarring.

The remaining task was to fill and seal the few tiny cracks on the knife coin.

Su Yuan did not use epoxy resin, but used the old method of shellac solution, because epoxy resin is not as permeable as shellac.

That's too overpowering for heavily mineralized bronze objects!

If you force it in, you'll bring down the fragile rust layer along with it, which would be counterproductive.

Two more days passed before all the reinforcement and filling were completed. Su Yuan placed the coin under the work light and carefully inspected it from all angles.

The mineralization department has finally stabilized!

The crisscrossing cracks on the blade were sealed up, but the seams were still clearly visible; there was no deliberate attempt to cover them up.

To his surprise, the deep, antique mercury hue actually became even brighter after the reinforcement.

The blue-green rust on top also shimmered under the light!

Su Yuan held the knife-shaped coin in his palm and quietly felt an extremely faint vibration emanating from it.

Like a taut string finally released, it's the feeling of tension vibrating in the air. Like a breath, compressed by rust for over a thousand years, finally finding its outlet!

Su Yuan saw the light in the bronze mirror flicker, and the halo on the mirror surface brightened a bit, as if a person was nodding.

He carefully placed the knife-shaped coins back into the brocade box, closed the lid, tidied up his tools and the table, and after washing his hands, he first called the man surnamed Zhao.

The owner of the knife coin must have been extremely anxious these past few days!

Hearing the words of gratitude on the other end of the phone, Su Yuan felt very happy. Then Xiao Jue's voice rang out:

"Master Su, you've been so careful these past few days, we haven't dared to breathe too loudly..."

"Yeah, we were all worried for you."

The Buddha statue and the lion heads on the balustrade also echoed this sentiment. Su Yuan smiled, stretched a few times, and stared at the Awu terracotta figurine for a few moments.

I went out to mail the knife-shaped coins, and instructed SF Express to expedite the process, telling them to take extra care to protect the item!

After resting in his office for a while, he opened his backpack, took out his great-grandfather's letter and bronze medal, placed them on the table, and read them again.

I haven't had a chance to check these past few days. I've been either fixing my coins or being dragged out for barbecue by Chen Xiaohe. It feels like these past few days...