Old Harden, can you handle having your vision-shifting abilities on all the time?

The process is similar to that of the Qianlong celadon gourd-shaped bottle, with the biggest challenge being the restoration of the sky-blue color in the glaze.

Although it's not quite the same as the gourd bottle situation, with the help of X-ray vision, we can still figure it out little by little.

For the next three days, Xu Xing practically lived in Restoration Room 0.

Similar to the efficient process used in restoring a Qianlong celadon gourd-shaped vase, the process involves cleaning the broken edges, aligning and bonding the parts, and replacing any missing components.

With the aid of X-ray vision, these steps, though tedious, are carried out in an orderly manner.

Xu Xing spent a day and a half restoring the shape of the vessel. The industrial-grade 3D scanner that was brought in accurately captured every curvature of the fingernail-sized defect at the mouth of the bottle. The printed porcelain blank was then meticulously repaired, bisque-fired, and joined by hand, and it fit perfectly with the original as if it had never been missing.

The real challenge lies in reproducing the glaze color.

The sky-blue color of the imperial kilns during the Yongzheng reign was far beyond what later generations could simply describe as bean green.

The test data that Chen Ming obtained from the provincial museum using his connections showed that this glaze color was extremely unique.

The glaze layer utilizes a complex color-developing mechanism formed by ferrous oxide and cobalt oxide, supplemented by trace amounts of rare earth elements for color adjustment, achieving a delicate balance in glaze layer thickness control between 0.25 and 0.35 millimeters.

And a unique microstructure between the glass phase and the crystalline phase, formed under a special cooling curve in the later stage of firing.

Countless tiny, dust-like calcium feldspar microcrystals are evenly suspended, with a size between 0.5 and 2 micrometers, which sharply scatter light, creating that visual miracle of clarity containing a hazy moisture.

What's even more challenging is that, even among porcelains from the same Yongzheng imperial kiln, different batches or even different locations within the same kiln can have subtle differences in color due to slight variations in kiln temperature, atmosphere, and glaze mixing.

The kiln's unique characteristics, achieved through such demanding restoration techniques, result in each piece possessing its own distinct color.

This is also the biggest challenge in the restoration of celadon porcelain from the Yongzheng period. Different types of porcelain require different fine-tuning formulas, which can stump 99.99% of restorers nationwide.

On the long worktable in the restoration room, there are more than two hundred unglazed porcelain test pieces, each about the size of a thumbnail.

Each tablet represents a recipe trial.

Xu Xing stood in front of the glaze mixing table, his white coat cuffs stained with various mineral powders. With his left hand on the precision electronic balance, he carefully added various raw materials by operating the feeding machine with a single feeding accuracy of up to milligrams with his right hand.

Basic feldspar glaze, quartz, kaolin, calcite...

Then comes the most crucial colorant: cobalt oxide powder, a bluish-black color; adding even a trace of it creates a deep, dark effect.

Ferrous oxide powder is dark green and is the main source of cyan, but it is very easy to oxidize and turn yellow.

To adjust the subtle dewy effect in the hue, he also added a trace amount of copper oxide.

Finally, there were those few grams of rare earth oxides that were specially approved.

Cerium oxide can enhance the opaqueness and jade-like texture of the glaze, while cerium oxide can make the blue color brighter, and neodymium oxide can produce a very faint purplish-red hue under certain lighting conditions, neutralizing any unnatural shine.

He meticulously recorded each recipe in his notebook.

Then, the pulp is prepared, applied to test pieces, placed in a miniature electric kiln, and the firing curve is set.

The firing temperature of Yongzheng imperial kilns is about 1280-1300 degrees Celsius. However, the temperature cannot be raised to this level during restoration. Otherwise, after applying the glaze to the damaged area of ​​the original piece, firing the original piece in an electric kiln may cause unpredictable damage. Therefore, the overall temperature must be controlled within 1200 degrees Celsius and the duration must be controlled within one minute.

Therefore, the preparation of glaze is more complicated.

During the hours of waiting for the glaze to be fired, he activated his X-ray vision and combined it with a specially modified high-magnification magnifying glass to penetrate the kiln wall and observe the entire process of the glaze melting, flowing, and crystallizing.

These eyes allowed him to see a microscopic world that ordinary restorers could hardly imagine.

How does the glaze begin to soften at 800℃ and completely melt into molten glass at 1100℃?

How cobalt oxide ions migrate and aggregate to form color centers.

Trace amounts of rare earth elements act like the most meticulous colorists, adjusting electron transitions at the atomic level to alter the absorption and reflection of light.

The most crucial aspect is how the anorthite microcrystals nucleate and grow in the temperature range of 900-750℃. Their state, quantity, and uniformity of distribution directly determine whether the final glaze is clear or cloudy, lustrous or dull.

The first batch of fifty test pieces were produced. When compared with the original under a standard D65 light source, the color difference ΔE of all of them was greater than 3.0, a difference that could be seen with the naked eye.

Some are too gray and lack spirit, some are too green and appear gaudy, and some, although similar in color, have an overly bright glaze and lack the warm and restrained luster of genuine pieces.

Undeterred, Xu Xing input the data into the computer and used software to analyze the trends, adjusting the formula based on the microscopic structural differences observed by his X-ray vision.

He soon discovered that the ratio of cobalt oxide to ferrous oxide in the glaze of the original piece was not fixed, but rather exhibited a certain gradient distribution, and that the microcrystal size was not completely uniform, but rather had a reasonable natural distribution.

This means that perfect reproduction is not about pursuing absolute uniformity, but about recreating the natural changes that feel alive.

The second batch of eighty test pieces had a color difference in the range of ΔE 2.0-1.5, which was already extremely difficult to distinguish, but Xu Xing was still not satisfied.

He felt that the glaze lacked moisture and the blue color appeared dry.

He concluded that the size distribution of the microcrystals was not close enough to the original component, which might be related to the cooling curve.

He adjusted the electric kiln program, adding a five-minute short-term heat preservation platform at 850℃, allowing the microcrystals more time to grow and adjust.

In the third batch, he boldly tried an approach not seen in previous literature, adding a trace amount of tin oxide to the basic formula.

Tin ions can alter the network structure of glazed glass and affect the precipitation behavior of microcrystals. At the same time, he further refined the ratio of cerium oxide and tin oxide, aiming to create a sense of depth with a faint bluish hue and a subtle skylight effect.

On the evening of the third day, the test piece numbered TY-119 was taken out of the kiln.

Xu Xing placed it side by side with the remaining glaze on the belly of the original Yuhuchun vase.

Under natural light, sidelight, and transmitted light, the difference is almost imperceptible to the naked eye after repeated comparisons.

He used a colorimeter, and the ΔE value was 0.7.

By activating X-ray vision to observe the microscopic level, the similarity of glaze thickness, bubble distribution, microcrystal size and arrangement density exceeds 95%.

It is it.

Once the final formula is determined, the subsequent glazing, firing, crease filling, and gap filling become very simple.

But Xu Xing knew that patience was needed most at this time. He used the finest brush to apply the glaze in layers, each layer being only tens of micrometers thick, and dried at a low temperature.

Finally, based on the TY-119 formula, a final fine-tuning was made according to the thickness of the body and the curvature of the surface at the glaze repair area to ensure that the glaze surface appears to be of uniform thickness and has a natural color transition after firing.

The final firing took place late that night.

When the electric kiln completed its cooling process and the kiln door was opened to dissipate the heat, the broken Yuhuchun vase stood before us again as dawn broke in the east.

Xu Xing let out a long sigh of relief, his eyes bloodshot, but his spirits were unusually high.

After completing the final repairs, he looked at the elegantly shaped, smoothly flowing Yuhuchun vase, its joints seamless, and the minor traces of the repaired seams barely noticeable under strong side lighting.

He let out a long breath.

The sky-blue color on the bottle after the rain seems to condense the clear sky after the rain in Jiangnan. The precious luster of the glaze is perfectly integrated with the original glaze that has not been restored.

It absolutely meets the national first-class compliance repair standards!

He carefully placed the bottle in protective gear, set a timer for constant temperature and humidity maintenance, and then lay down on a makeshift cot in the corner of the restoration room and fell into a deep sleep.

the next day.

He was awakened by a knock on the door.

When Xu Xing opened his eyes, it was already 10 a.m. He got up and opened the door. Wang Ben was standing outside, followed by Chen Ming, who looked a little flustered.

"XCMG, did I disturb your rest?"

Wang Benquan smiled broadly, carrying an exquisite food box in his hand, and said, "I just came back from a business trip to Jingdezhen. Team Leader Chen told me that you've been working tirelessly in the restoration room these past few days, you've really worked hard!"

"Don't rush with that Yuhuchun vase. The sky-blue glaze of the Yongzheng Emperor is notoriously difficult to work with. Many master craftsmen spend months adjusting the glaze and still can't get the hang of it. Don't feel pressured, take your time. We have plenty of time..."

As he spoke, he placed the food box on the table beside him, opened it, and said, "I brought you some breakfast, while it's hot... Hmm?"

Wang Benquan's words came to an abrupt end.

His gaze fell on the specially made glass protective gear on the worktable in the middle of the restoration room.

The slender and elegant jade vase inside the protective gear was quietly bathed in the morning light filtering through the blinds, its entire body shimmering with a captivating sky-blue luster.