With a crisp sound of "Hua Hua", the best charcoal was sent into the stove. The air passed through the tunnel and continued to drill into the ash leak, and soon a piece of orange-red щww{][com}

With a strange mood, Han Cheng personally poured two cans of crushed mineral powder into the large vat. The two cans weighed about thirty kilograms.

The Qingque tribe’s copper smelting business thus began.

The thermal conductivity of pottery is much worse than that of metal. However, at that time Han Cheng did not have the ability to make a steel boiler or other metal boilers that were more heat-resistant and had better thermal conductivity, so he could only slowly make pottery jars.

"Add carbon to it and bring the wind grunt over."

After waiting for a while, Han Cheng saw that the mineral powder in the pottery jar did not show much sign of melting, so he thought about it and gave this order.

"Chi~chi~, chi~chi"

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

Before long, hot flames rose from the stove. The fire was much bigger than before, and the charcoal in the middle was red and white.

These efforts were not in vain. This state lasted for about thirty minutes. Han Cheng found that the mineral powder in the pottery jar seemed to have become lower.

As time went by, this feeling became more and more obvious, and finally, sticky red liquid metal appeared before his eyes, slowly swallowing up the dust-like ore powder.

Han Cheng, who was sweating due to the high temperature, couldn't help but reveal a look of joy.

He didn't expect such gratifying changes to occur after his first smelting of copper ore.

The witch also came over and stretched his neck to look inside, with a look of joy on his face. Although he didn't see much, it didn't stop him from being happy with the Son of God.

Several senior brothers who had built a shed around the furnace came over to watch like witches, and were amazed at the amazing transformation of stone into water.

Fantasizing that the tribe would get a large number of metal tools, they felt full of energy. After standing here and watching for a while, they worked even harder to build the shed.

As time passed, the mineral powder melted more and more, and finally all became a sticky, dark red liquid metal.

Han Cheng, who was looking at all this with great joy, suddenly became unhappy because at this moment he suddenly realized that he had overlooked a very important thing.

That is how to get the molten metal ore out of the big vat.

It would have been best to make a hole at the bottom of the pottery jar and let the molten metal flow out through the hole, but it was obviously impossible to do so at this time.

Han Cheng scooped it up with a ceramic spoon with a wooden handle, and looking at the metal beads dripping everywhere, he gave up the idea of ​​scooping them out with the ceramic spoon.

After thinking about it, he asked people to stop the fire and stop adding charcoal to the stove, and also stopped the wind from turning.

As the temperature inside the stove dropped, after a short while, the bright red molten metal in the vat began to turn dark red, and eventually cooled down and turned solid again.

The witch who came over to watch had a big smile on his face, and the eldest brother and others also grinned.

Because there was a large piece of metal in the pottery jar, the metal looked black and somewhat similar to iron.

The tribe has been searching for iron bacteria for such a long time, but the iron they have obtained is very limited. The iron boiled in this jar seems to contain more than all the iron tools the tribe has combined. How can they not be happy?

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

What appeared before my eyes looked like slag no matter how I looked at it.

Han Cheng couldn't help sniffing. He found that he had made another serious mistake, which was not separating the molten copper from the slag.

The two are inseparable, so it would be difficult to obtain pure copper.

"Smash it."

After waiting for a while, when the temperature dropped even lower, Han Cheng had the large vat taken down from the stove.

After turning the vat upside down and banging it on the ground for a while, he saw that the mixture of copper and slag inside had solidified into a block and there was no sign of it falling out, so he ordered someone to smash the vat.

There is no Sima Guang in the tribe, but they can still smash the jars just as cleanly and efficiently.

These people, who were stimulated by metal and were as excited as chicken blood, smashed the jar into pieces in a few strokes after receiving Han Cheng's order.

Then the stuff that was solidified inside came out.

This is a cylinder in the shape of a tank bottom. The bottom is purple metal and the top is black slag that feels loose to the touch.

The purple metal is pure copper that has been refined.

Han Cheng found some stones and smashed them for a while, and he did manage to knock off some of the slag, but it was impossible to separate the slag and copper completely in this way.

If you want to separate the two completely, you have to do it when they are in a state of tension.

After watching for a while with some regret, Han Cheng no longer felt sad about the failed refining, because before refining, he had not thought about being able to succeed in one go.

And this time the copper smelting was not completely fruitless. Han Cheng discovered that a hole had to be left at the bottom of the large refining vat, and that the slag was lighter than copper and would float on the molten copper after melting.

With these two discoveries, it becomes easier to separate slag and molten copper.

"Son of God, here!"

The third discovery soon appeared, which was still a shortcoming.

Heiwa pointed at the stove and spoke to Han Cheng.

As the charcoal fire died down, the stove gradually cooled down.

Han Cheng looked over as Heiwa pointed out, and saw that many bricks inside the stove had been connected together. The surface was smooth and felt a bit like ceramic tiles.

This is the effect produced when the temperature inside is too high and the bricks cannot withstand it, so they slowly melt and then cool down.

"Tear down this stove!"

Han Cheng's face suddenly turned pale as he touched the smooth bricks, because he thought of a terrible scene -

As the charcoal continued to burn, the bricks that made up the stove gradually melted and became softer and softer, and then they could no longer bear the weight and fell apart.

A large vat filled with half a tank of molten metal tilted and fell, and the molten metal at a terrifyingly high temperature quickly rolled out and landed on people...

Just imagining such a horrific scene makes people shudder, especially for those who have just been standing next to the stove for a long time.

Heiwa and his companions didn't know why the Son of God had people tear down this good stove. In their opinion, this was a very good thing, because not only did it look good, but the entire stove also looked more solid.

Their doubts only lasted for a short time. After listening to Han Cheng's description of the horrific scene, they no longer thought it was a good thing.