Chapter 47: Six Fillings and Six Firings

With a soft "ding," Lin Sicheng came out of the testing room, carrying a lobed tray.

Shang Yan came back to her senses, pulling her back away from the chair, wearing an extremely strange expression.

Not yet knowing that Wang Qizhi had completely sold him out, Lin Sicheng felt quite puzzled: He had merely operated the machine, so why would it shock Professor Shang to this degree?

"Professor Shang, what's wrong?"

"Nothing at all!"

"Oh, then should I go mix the glaze?"

Was she even pretending anymore?

At the very least, shouldn't she check the logs, verify if there were errors in voltage excitation, check if the signal was stable, or see if the calibration curve was abnormal?

Muttering inwardly, Shang Yan glanced at the computer monitor: Forget it, what was the point of looking?

Every single value in the report looked as normal as if someone had filled them in by hand.

Seeing that she remained silent and taking it as consent, Lin Sicheng pointed to the material box brought from Wang Qizhi's laboratory:

"Assistant Feng, please prepare the materials."

"Oh, right away..."

Having long been stunned into a daze and shrinking quietly in the corner like an invisible person, Feng Lin hurriedly stood up.

"Senior Sister Li, prepare the glaze... Senior Sister Li?"

After being called twice, Li Zhen finally snapped out of it, looking as though she had just woken from a deep sleep.

That was entirely normal; she had been numbed by shock...

Lin Sicheng glanced at her, then tapped the table: "Take notes!"

Li Zhen's face flushed slightly as she hurriedly grabbed paper and pen.

"Base glaze: Natural mineral materials: 40% red lead, 20% borax, 10% each of quartz and feldspar... Oxidizing agents: potassium oxide... calcium oxide... cobalt oxide... copper oxide... iron oxide... arsenic oxide...

Key points: Melt at 900 degrees Celsius in a furnace, quench in water to form granules, grind to above 200 mesh..."

"Colored glazes: First, deep green, mixed according to eight tonal ratios: copper oxide, iron oxide... then medium green... then light green... temperature 800, oxygen-enriched firing, form granules, grind to 200 mesh..."

"Second, light pink... Third, golden yellow... Fourth, crimson... Fifth, bright silver..."

"Assistant Feng, prepare the copper base... dimensions... thickness... tempered purple copper wire, width... length... also prepare white hyacinth mucilage and quick-drying adhesive..."

Just as Lin Sicheng began listing items, Wang Qizhi was taken aback: Why did these proportions completely mismatch the test analysis report?

Looking at the original artifact's glaze sample test: feldspar accounted for a full 35%, yet in Lin Sicheng's glaze formula, it was only 10%?

In the report, borax was only 5%, but in the new formula, it accounted for a full 20%.

Especially the red lead, which was only 10% in the original glaze, but accounted for 40% in the new formula?

The crucial point was that Wang Qizhi could not remember any copperware or porcelain whose glaze was formulated this way: using more red lead and borax than feldspar and quartz?

Frowning, just as he was pondering the underlying principles, a murmur like sleep-talk reached his ears.

"He actually knows how... He actually really knows how?"

Turning his head to look, Shang Yan had her eyes wide open, her gaze fixed like hooks onto Lin Sicheng's face.

Wait... your teaching assistant acted like this, and you're doing it too?

Was there any need to be this exaggerated?

"Professor Shang... Professor Shang?"

"Oh, oh... Professor Wang, please go on."

"Why is this glaze formula so bizarre?"

Shang Yan let out a long sigh: "It is indeed bizarre, but it's correct!"

Wang Qizhi was stunned: "What kind of logic is that?"

"First, it acts as a flux; second, it strengthens the structure; third, it maintains the fluidity of the glaze during cloisonné infilling; and most importantly, it matches the copper base, adjusts the thermal expansion coefficient of the glaze, and lowers the furnace temperature during the secondary firing as much as possible...

I estimate that the furnace temperature during restoration will not exceed 700, and should basically be controlled between 650 and 700. The possibility of secondary cracking in the original glaze layer is very low..."

Wang Qizhi understood instantly: If the glaze were repaired according to the formula in the test report, the furnace temperature would have to be at least 800 degrees, which would definitely crack the original glaze layer. Therefore, Lin Sicheng simply reformulated the glaze to lower the furnace temperature.

"But in that case, it's equivalent to diluting the base glaze multiple times. How can color expression, glaze luster, and texture be guaranteed?"

"That's why he additionally prepared five colored glazes... which means he will have to fill the cloisonné at least six times and enter the furnace six times... achieving consistency with the original glaze layer through gradient effects..."

Pausing slightly, Shang Yan furrowed her brows again: "But as far as I know, to this day, only Professor Yang Shiqi and Professor Qi Haonan from the Palace Museum used a similar method when restoring the Qing dynasty copper-gilded transparent enamel flower basket table clock... Aside from that, there has never been another case..."

Now Wang Qizhi understood why Shang Yan had been shocked to that extent: This method was difficult—extremely difficult, in fact.

Though he considered himself a layman, that was only relatively speaking. At the very least, he was well aware of the impact temperature had on coloring oxidizing agents and tonal changes.

A difference of just one degree in temperature could result in a color rendering coefficient difference of over a dozen degrees after sintering.

Wasn't this equivalent to multiplying the restoration difficulty of this plate many times over?

As for whether it would succeed... Judging by Shang Yan's ghost-like expression, Wang Qizhi's intuition told him it was unlikely.

Yet, combined with his understanding of Lin Sicheng: the more impossible you thought it was, the more likely he was to pull it off...

While he was guessing wildly, a "crack" sound echoed in his ears. Wang Qizhi raised his head, his eyelids twitching uncontrollably.

Had Lin Sicheng actually pried off the fish tail from the bottom of the plate?

Wait... you haven't even started repairing it yet, and you're already doing demolition?

"Lin Sicheng, what are you doing?"

"Testing the safe temperature range for the furnace, of course," Lin Sicheng said with an expression of complete reasonability. "Didn't we agree on this earlier?"

They had indeed agreed, but you didn't say you were going to pry off such a large piece!

Never mind, it was already pried off anyway. Even if he failed to fix it, Professor Lin was still there as a safety net...

Wang Qizhi waved his hand, signaling him to continue.

Lin Sicheng proceeded methodically: composition, pattern design, filigree bending, adhesion, soldering, correction... basically copying the pattern from the bottom of the plate, using copper wire to piece together and replicate the two fish patterns onto a new copper plate.

Simple as it sounded, it still left Wang Qizhi and Shang Yan dumbfounded.

First, precision: with a stroke and a snip of the pliers, followed by a bend of the tweezers, he instantly formed the required arc, and upon sticking it onto the copper plate, it fit with absolute perfection.

According to Lin Sicheng's instructions, Feng Lin was supposed to trim excess wire ends or fill in microscopic gaps. Yet, by the time the two fish were almost fully assembled, she had just stood there without getting a chance to lift a finger.

Second, speed: from sketching the base drawing to soldering and correction, he pieced together over a hundred copper wires of various sizes in less than an hour.

The crucial part was that the proportions matched the original bottom pattern almost one-to-one... It felt as though Lin Sicheng had a ruler built right into his eyes.

After watching for a long time, Shang Yan sighed again: "Professor Wang, if you were to do the filigree work, how long would it take you?"

Two to three hours, I suppose...

Subconsciously turning the thought over in his mind, the words already rushed to his lips, but Wang Qizhi's tongue suddenly took a sharp turn: "Who would need hours?"

Shang Yan was momentarily stunned, then curled her lip: Self-incrimination!

I asked how long, who asked you about hours?

Just in time, Li Zhen had finished preparing the base glaze, and Lin Sicheng began applying the colored enamel. Shang Yan and Wang Qizhi focused intently, not even daring to blink.

Seeing the enamel-filling tool in his hand move as though an extra finger had grown, with the glaze powder possessing a spiritual intelligence that automatically flowed to exactly where it belonged, Shang Yan felt completely drained of any desire to complain.

She had just been laughing at Wang Qizhi, but looking at it now, it seemed she wasn't much better off herself.

As she was sighing inwardly, Lin Sicheng instructed Li Zhen to ignite the furnace. Shang Yan narrowed her eyes: The most crucial part was about to begin.

Filling the glaze, entering the furnace, firing, natural cooling, opening the furnace... filling the glaze again, entering the furnace again...

Repeating this back and forth a total of six times, it was already the second day.

Actually, by the enamel-filling stage, assistants were no longer strictly needed, but neither Feng Lin nor Li Zhen left. At most, during the three-plus hours of each cooling cycle, they took turns dozing off in the adjacent lounge for a quick nap.

Shang Yan and Wang Qizhi had no choice: they couldn't possibly cancel all their classes for two days straight, could they?

Yet, timing it precisely, they rushed into the conference room just before the final furnace opening.

Only Li Zhen and Feng Lin were in the laboratory, their heads pressed close together, staring intently at the lobed tray on the table as if studying some profound mystery.

"Did we come early?"

Exchanging a glance, Wang Qizhi looked around. "Where is Lin Sicheng?"

Li Zhen and Feng Lin hurriedly stood up and greeted them: "Professor Wang, Lin Sicheng went home this morning."

Wang Qizhi froze: "What?"

"He went home... Right after the final furnace entry, while you were in a meeting, he didn't dare call you... But he left instructions before he left:

When the time was up and it cooled down to room temperature, we just needed to open the furnace, place the pattern at the bottom of the basin, and take a photo for him. If there were any issues, he would come over immediately... We already took the photo, but he didn't come..."

Which meant there were no issues?

Wait... how could this kid be so bold?

Even if it was just a sample, they had slogged through a full two days...

Muttering curses under his breath, Wang Qizhi walked over to the workbench and cast a casual glance, but his eyelids immediately started twitching uncontrollably:

The interior of the basin shimmered with blue hues, two koi fish chasing each other tail-to-head, one with head and tail of glowing gold, its dorsal scales shimmering with starlight. The fish's head poked out of the water surface, stirring up ripples...

The other fish transitioned from red to pink, its body slightly arched, its tail stirring up a tiny vortex, with a few silver-foam-like water droplets suspended mid-air.

Beauty and aesthetic appeal were secondary; what truly struck one was the sense of vividness, vitality, harmony, and seamless integration... Wang Qizhi felt that the two fish at the bottom of the basin were naturally meant to look precisely like this.

He even felt a trace of regret; had he known it would be this successful, he would have let Lin Sicheng repair the original directly instead of wasting time test-firing a sample.

Sighing, he prepared to ask Shang Yan for her critique, but the moment he turned his head, he jerked backward in shock: Wait, Professor Shang, aren't you being a bit too exaggerated?

She stood completely motionless, eyes unblinking, looking as though she wanted to pluck her own eyeballs out and embed them into those two fish.

And she was chanting under her breath: "Six fillings, six firings... That clock at the Palace Museum was only fired five times..."