In the instant when Old Zhong's half of the blade in his hand snapped.

The entire courtyard suddenly plunged into silence.

The air froze, and even a pin drop could be heard.

Indeed.

Because the horseshoe has a certain thickness.

When the short knife contacts the horseshoe, the short knife gains no advantage and is inherently at a certain disadvantage.

But don't forget.

This knife of Old Zhong is not an ordinary knife, Old Zhong once used it to break through heavy cavalry heart protection mirrors!

If he weren't the grandson of Zhong Shiheng, and had made great achievements as the Jingyuan Prefecture Commander.

He would have had no chance of obtaining a weapon of this material.

Soon after, Old Zhong was silent for a moment.

He didn't bother with the blade head on the ground but instead put down the knife handle and picked up the horseshoe on the table.

At that moment.

In the area where the horse iron hoof and the knife tip met, apart from a very slight white abrasion, no nick was visible.

Seeing this, Old Zhong's breath momentarily halted.

Then he abruptly looked at Xu Yun, his beard briefly floated in the air for half a second, and he asked:

"Mr. Wang, how many of these iron tools can you forge?"

"The Imperial Envoy can call me Xiaowang."

Xu Yun respectfully cupped his hand toward Old Zhong, showing deference to the veteran general no less than Wang Bing:

"As you can see, as long as the iron ore quantity is adequate, we can forge as many as needed."

Old Zhong pondered for a moment, then turned to eye the coffin-like reflecting furnace and pointed to the magnesium brick at the top:

"If I'm not mistaken, this should not be ordinary clay bricks, I wonder about its material..."

Xu Yun thought for a while and said:

"Please wait for a moment."

After speaking, he went to an area by the wall where materials were stored, lifted the shading cloth, and searched it briefly.

Shortly thereafter.

He came back holding a white mineral.

He handed the mineral to Old Zhong and asked:

"Imperial Envoy, do you recognize this item?"

Old Zhong took the mineral, looked at it for a few moments, stroked his beard, and uncertainly said:

"If I'm not mistaken, this seems to be... porcelain ash stone?"

Xu Yun nodded affirmatively:

"Correct, it is porcelain ash stone, a common mineral seen everywhere on Qinfeng Road."

"We only need to calcine it at high temperatures, then crush it and compress it using brick-making methods, and magnesium bricks can be easily prepared."

Old Zhong's pupils contracted again.

As an old general who has fought on the western line for years, he is very familiar with this stone:

Searching outside any camp on the western line for half an hour, unless you're possessed by a Kunlun Slave, you will certainly return with a large basket of porcelain ash stone.

In western line fortifications.

This mineral, being extremely fragile, is not even considered scraps, specifically used to house prisoners.

What Old Zhong isn't aware of is.

The so-called porcelain ash stone is the later known magnesite, one of the minerals with the highest reserves in our country.

Two-thirds of the world's magnesite reserves are concentrated locally, totaling over thirty billion tons.

Which means.

The seemingly most special material in the whole iron-making process is in reality an extremely easily accessible resource!

Of course.

Strictly speaking.

In the entire process, the pure oxygen preparation step is technically the hardest, involving many chemical reactions and even electrical issues.

But given that Old Zhong hasn't been exposed to the microscopic field, Xu Yun didn't touch upon it too much.

This is also part of the confidence he maintains to keep the technology from being revealed.

After all, whether it's the military or the court, their scale wouldn't worry too much about the depletion of common resources, because they are confident of exchanging for greater benefits.

Then Old Zhong glanced again at the break in the knife handle in his hand, turned to make eye contact with Wang Hou, who was a bit older beside him.

The two older generals over fifty mutually saw the same idea in each other's eyes with extreme tacit understanding.

Then, Old Zhong lightly coughed and asked Xu Yun:

"Prince... Xiaowang, considering this, may I say..."

"If the iron ore is sufficient, you can produce countless molten iron, and aside from horseshoes, you can also forge knives or armor of the same material?"

Hooked.

A trace of a curve appeared at Xu Yun's mouth corner but he quickly suppressed it.

He touched his nose and replied seemingly casually:

"Correct, weapon and armor are just mold problems, unrelated to the craftsmanship."

"If the Imperial Envoy is willing, making an iron house is no problem, likewise as sturdy as the horseshoe."

This time, Old Zhong's expression didn't falter, but his left hand holding the knife handle instantly exerted a little more force.

It truly is possible!

One must know.

Like the horses.

In the western line... or say on all battlefields throughout history, the attrition of weaponry and armor is likewise a significant concern.

Taking Emperor Wu of Han's expedition against the Xiongnu as an example.

According to records in the "Comprehensive Canon."

Up to the time before Huo Qubing's sealing at Langju Xu, within Han's military provisioning, 'weapons were replaced forty thousand times', "foot soldiers rotated numbering hundreds of thousands in the army."

Before sealing Langju Xu, Huo Qubing and Wei Qing each led an army of fifty thousand, meaning fifty thousand consumed two hundred thousand weapons—actually, assessing from later achievements, Huo Qubing likely consumed more resources than Wei Qing.

Additionally worth mentioning.

The "Comprehensive Canon" documents weapon quantities as "times."

In other words, excluding bows and arrows, mainly referring to knives, spears, swords, etc.

At that time, Huo Qubing mainly engaged the Xiongnu Left Prince's Division, inflicting a loss of ten thousand while killing seventy thousand, during a penetration of over a thousand miles, undertaking eight large-scale battles of thousands and more than a hundred small battles.

If one casually counts ten minor battles as one major, then on average, every three major battles would result in a weapon being destroyed.