With the experience of smelting copper for the first time, the firing technique of Pear Blossom and others is obviously more proficient than the last time, and the cooperation between everyone is also more tacit.

The melting point of tin is very low, and the sulfides and impurity metals with high melting points in the ore are already fished out as slag before they are mixed into the tin water.

In this era, there is no need to consider the reuse of metal slag and exhaust gas reheating, and this extensive production model will continue for at least a few hundred years.

Due to the limited manpower, the Ewha group could only smelt copper for a few days and tin for the next few days, and when all the ore was smelted into metal ingots of about the same size, the smelting of bronze officially began.

Gu Guo used a pottery crucible to receive a bronze solution, and the copper-to-tin ratio is four to one, and the melting point of bronze is about 800 degrees Celsius, and the temperature that the pottery crucible can withstand is at least 1100 degrees Celsius.

The bronze is poured into a pre-fired mold with a crucible and cooled to obtain a rough bronze.

Rika is holding the crucible with tongs, and is carefully pouring a spoonful of bronze juice into the hoe mold, and so on three times, and the mold is finally filled with bronze.

There was only one forceps, and now it was used by Gu Guo for emergency, so only one person was pouring it.

A crowd gathered around the molds and furnaces, whispering about the metal that would later change their way of life.

Although the pottery crucible can withstand the high temperatures of bronze, the pottery is not as strong as steel, and it can still maintain its shape intact after thermal expansion and contraction.

In order to prevent the crucible from exploding and the high-temperature bronze liquid splashed on the clansmen, Gu Guo kept staring at the movements of the pear blossoms all the time, and he had to be careful at any time when the clansmen came close to observe.

The fineness of the bronze tools is not as fine as the ceremonial utensils, so Gu Guo did not specifically collect beeswax and cast bronze with the lost wax method.

Tools such as hoes, axes, and shovels were crafted through the efforts of the clansmen, and with these tools, the mining of minerals and the construction of walls were several times faster than before.

The first to be updated was the spear of the tribe, which was sharper than the stone spear when it was struck with sandstone, and completely crushed for durability.

In addition, Gu Guo also poured a small number of bronze arrow clusters to deal with large beasts and future hostile humans.

glanced at the attribute bar, and the contribution points broke 1,000 again!

"Name: Gu Guo

Civilization Contribution Points: 1526

Civilization: Early Bronze Age

Unlocked Technologies: Neolithic: Pottery (36), Salt (12), Bow and Arrow (108), Net (33), House (135)

Bronze Age: Copper (400), Pottery (850), Tin (300), Bronze (640)"

The personal page has been updated again, and the era of unlocking technology is divided into two.

"There are not as many contribution points as pottery coins from unlocking bronze, and the currency is not a product of the Neolithic Age, but a product of the Bronze Age?"

Looking at the neatly stacked bronze tools in the room, Gu Guomo rubbed his chin and pondered.

He only remembered that the earliest currency in his previous life was supposed to be the shells of the coastal areas, which was in the Xia Dynasty, when the Late Neolithic period bordered the Early Bronze Age.

Perhaps it was the system that determined that artificial coinage was considered currency, so currency did appear in the Shang and Zhou dynasties, when bronze was prevalent, and the flower growers at that time already owned copper shells made of copper.

The system store has also undergone an update, and Gu Guo found that he can now exchange not only technology and knowledge, but also a column of materials.

"Technical:

Pottery (mastered), salt (mastered), charcoal burning (mastered), house building (mastered)

......”

"Knowledge:

Basic botanical knowledge (46.9%)

Simple zoological knowledge (not mastered) contribution points: 1000

Simple knowledge of geology (not mastered) contribution points: 1000

Simple mineralogy knowledge (not mastered) contribution points: 1000

Simple astronomy knowledge (not mastered) contribution points: 1000

......

"Supplies:

Copper (Bronze Age) contribution points: 300/t

Tin (Bronze Age) contribution points: 200/t"

"The system is really open!"

Looking at the materials that could be exchanged, Gu Guo was dumbfounded, although it was not as good as the one-click decomposition and one-click synthesis ability of other systems, but if he could exchange these two materials, the development speed was the same as opening an accelerator.

As we all know, the metal produced by the local copper smelting and tin smelting contains a lot of impurities, including trace amounts of lead, iron, gold, silver and a bunch of sulfides, silicides, etc., and the metal exchanged by the system is a simple substance with a purity of 100%!

With Gu Guo's current contribution points, it is completely possible to use the exchanged copper and tin to refine 5.45 tons of bronze according to the ratio of four copper and one tin!

What is this concept?

Now in order to refine this ton of bronze, the tribe of Gu Guo has nearly forty people who have left food production.

Among them, there are 17 people who mine and transport ore, 11 people who burn charcoal in ore processing and crushing ore, and part of the smelting is drawn from the previous 11 people, plus the remaining nine people specialize in smelting, and a large group of people toss for a whole month to produce about a ton of bronze, which is only slightly more than the weight of Simu Wu Dafang Ding.

This is all the productive forces that the Gu Guo tribe can pull forward, and it can't be maintained for a long time. It was the end of spring, and the abundance of food for gathering and hunting in the wild had emboldened him to extract so many people to refine bronze.

This wave of exchange is equivalent to a direct fast-forward of several years.

As for how to explain to the clansmen how to exchange the two metals, it made Gu Guo difficult.

The story told is like spilled water, and in the long run, he didn't glorify himself as the son of a god, and he could cast spells.

Now, if these four or five tons of copper and tin inexplicably appeared in the vision of the clansmen, then the materialist worldview that he had spent most of the year instilling in the clansmen would collapse.

"Alas, it seems that the pit dug by yourself can't be buried!"

Sighing silently, Gu Guo picked up a bronze axe and rubbed the blade on the rough sandstone.

The bronze objects cast were all unbladed, and in order to really use the bronzes, they still needed to be polished, which took forty people nearly two days.

Pear Blossom and the others stroked the fruits of their labor in the past month, the golden metal showed a cold glow after the opening, and the fingers flicked, making a "bang" sound.

The miners waved their hawks-billed hoes, they had been fascinated by the luster of bronze for the past two days, and the stone tools that they had once treasured had been discarded and thrown aside.

"This thing called bronze is much more durable than stone!"

"It's definitely faster to dig than a stone!"

“......”

People were talking about bronze, and Gu Guo quietly slipped outside.

In the past two days, I found that the materials exchanged from the system store can appear anywhere within a radius of 100 meters around the traverser, but will not appear in the living body, which makes Gu Guo give up the way of using card bugs to solve the hostile traverser.

However, the system can be exchanged according to the kilogram, which is undoubtedly a good way for the current Gu Guo to settle for the second.

As long as he secretly added one or two kilograms of copper and tin to the furnace every time he smelted, he could increase his production over time.