In the crisp sound of "boom", the fine charcoal was sent into the stove, and the air passed through the tunnel, and continued to drill into the place where the ash leaked, and soon a fire of orange red was ignited.

With a strange mood, Han Cheng personally poured two jars of ore powder into the vat, which were about thirty catties.

The copper smelting of the Qingque tribe began.

The thermal conductivity of pottery is far worse than that of metal, but at this time, Han Cheng did not have the ability to make a steel boiler or other metal boilers that were more heat-resistant and had good thermal conductivity, so he could only come slowly with a pottery jar.

"Add carbon to it and get the wind to grunt."

After waiting like this for a while, Han Cheng saw that the ore powder in the pottery jar did not have much intention of melting, and after thinking about it, he gave such an order.

"哧~哧~,哧~哧"

The 'hand pressure drill' pressed up and down, driving the fan blades to rotate back and forth, continuously injecting wind into the stove through the clay pipe.

It didn't take long for a scorching flame to burst out in the stove, and the fire was much larger than before, and the charcoal fire in the middle was red and white.

These efforts were not in vain, this state lasted for about thirty minutes, and Han Cheng found that the ore powder in the pottery jar seemed to have become a little lower.

As time passed, this sensation became more and more pronounced, and eventually a thick, reddish molten metal appeared in front of the eyes, slowly devouring the dusty ore dust.

Han Cheng, who was sweating from the high temperature, couldn't help but show a happy look.

He didn't expect such a gratifying change in the first smelting of copper ore.

Wu also leaned over and stretched his neck to look inside, his face also showing joy, although he didn't see much, but it didn't prevent him from being happy with Miko.

The elder brothers, who had built a shed around the stove, also came over to watch like witches, and were amazed at the astonishing change of stones into water.

Imagining that the tribe would get a lot of metal tools, they only felt full of energy, and after standing here and watching for a while, they worked harder to build the shed.

Over time, the fines melt more and more, and eventually they all become viscous, dark red molten metal.

Han Cheng, who was overjoyed at all this, suddenly couldn't be happy, because it was only at this time that he suddenly realized that a very important matter had been ignored by him.

That is how to get the boiled metal liquid out of the vat.

It stands to reason that it is best to make an opening under the clay jar and let the molten metal liquid flow out of the hole by itself, but at this time, it is obviously impossible to open.

Han Cheng scooped it with a clay spoon with a wooden handle, and when he looked at the metal beads dripping randomly, he gave up his plan to scoop them out with a clay spoon.

After thinking about it, let people stop the fire, stop adding charcoal to the stove, and the wind does not need to turn anymore.

As the temperature inside the stove dropped, it didn't take long for the bright red molten metal inside the vat to turn dark red, and finally cool down and turn solid again.

Wu who came over to see had a smile on his face, and the senior brother and the others were also baring their teeth.

Because there is a large piece of metal in the clay jar, these metals look a little black, and some resembles iron.

How could they be upset that the tribe had been searching for iron bacteria for so long, and that the iron they had obtained was very limited, and that this vat seemed to have been boiled more than all the iron tools in the tribe combined?

They were happy, but Han Cheng couldn't, because copper didn't seem to have this color in his memory.

What appears in front of you looks like slag.

Han Cheng couldn't help but sniffle, he realized that he had made another serious mistake, that is, he did not separate the liquid copper from the slag.

The two are inseparable, so it is a little difficult to get pure copper out.

"Smash it."

After waiting for a while, when the temperature dropped even lower, Han Cheng asked the vat to be lifted off the stove.

He knocked it upside down on the ground for a while, and when he saw that the mixture of copper and slag solidified in it showed no signs of falling, he made a noise and asked people to smash the vat.

There is no Sima Guang in the tribe, but he smashes the cylinder just as neatly.

These people who were stimulated by metal like chicken blood, after getting Han Cheng's order, smashed this good tank to a pulp in three or two clicks.

Then what is solidified inside comes out.

This cylinder in the shape of a cylinder bottom is purple metal underneath, and slag on top is black-leaning and vague to the touch.

The purple-tinge metal is pure copper that is refined.

Han Cheng found a stone and smashed it for a while, but he also smashed some slag, but it was impossible to separate the slag and copper in this way.

The only way to separate the two is to do so while they are liquid.

After watching it with some regret for a while, Han Cheng didn't feel any more sad about this failed refining, because he didn't think about being able to succeed at one time before refining.

And this time the copper smelting was not for nothing, Han Cheng found out from the inside that there was a hole under the refining vat, and found that the slag was lighter than copper, and it would float on top of the copper liquid after melting.

With these two discoveries, it is easier to separate the slag from the molten copper.

"Miko, here!"

A third discovery soon followed, which is still a shortcoming.

Heiwa pointed to the stove and said to Han Cheng.

As the charcoal fire goes out, the stove gradually cools down.

Han Cheng looked over with Heiwa's guidance, and saw that inside the stove, many bricks had been connected together, the surface was smooth, and it looked like touching the tiles.

This is the effect of the temperature inside being too high for the bricks to withstand, and after slowly melting and cooling.

"Rip this stove!"

Han Cheng, who was touching the smooth bricks, suddenly turned pale, because he thought of a terrible scene because of this-

As the coals burned, the bricks of the stove gradually melted, became softer and softer, and then could not bear the weight on them and fell apart.

The vat containing half a cylinder of molten metal fell at an angle, and the molten metal containing the terrifying high temperature quickly rolled out and fell on the person......

Such a terrifying scene can make people shiver when imagined, especially for someone who has just stood next to the stove and operated it for a long time.

Heiwa and the others didn't know why Miko wanted people to pick up this good stove, in their opinion, it was excellent that such a situation occurred, because not only did it look good, but the whole stove also looked stronger.

Their doubts only existed for a short period of time, and after listening to Han Cheng's description of the terrifying scene, they no longer felt that this was a good phenomenon.