The Birth of Bronze
Wang Yan's team made it smoothly without encountering any other unexpected events. Following the description given by their leader, Lu Ming, they easily found the area known as "Colorful Stone Mountain." The terrain there was indeed quite unique, with rocks displaying mottled colors. Near the hillside and the dried-up streambed, they quickly spotted their target.
The malachite deposit is located on a sunny, gentle slope. The emerald green veins stand out against the grayish-brown rocks. Although it is not a rich deposit, the exposed ore is sufficient for them to collect. Another tin ore (mainly cassiterite) deposit is located in a ravine not far away on the other side of the mountain. It has a unique metallic luster and is also easy to identify and collect.
"Quick! Separate these green Shitou from those shiny, heavy Shitou!" Wang Yan commanded the soldiers, suppressing his excitement. Although they didn't understand why, seeing how much importance the wise man attached to it, they all worked extra hard. They used Shichui off large chunks of ore and carefully loaded them into the deep baskets on either side of the ox's back.
The work was highly efficient; in less than half a day, the loads for ten oxen were full. Considering that it was an inappropriate first experiment to be greedy and that they needed to return as soon as possible, Wang Yan ordered the collection to stop. In the end, they harvested about the weight of malachite carried by seven oxen and the weight of tin ore carried by three oxen. Without a moment's delay, the team immediately turned around and began their return journey.
With the help of oxen and horses, the return journey was faster than expected. On the afternoon of the fourth day, the caravan, laden with "Shitou," quietly returned to the Fire Tribe Valley. Wang Yan didn't even have time to rest; he immediately directed the Fire Tribe's trusted warriors to secretly transfer the ores to a newly built "secret forging area" located in the most secluded corner of the valley, guarded by special personnel. This was the Fire Tribe's newly designated absolute forbidden zone, which even many high-ranking members had never set foot in.
However, the real challenge was only just beginning. The first step was processing the malachite. Wang Yan instructed several of the most reliable and skillful craftsmen he had selected to carefully break the large pieces of malachite into smaller pieces, and then grind them into the finest powder possible. This step was extremely laborious, but they were patient.
Next, in a specially made ceramic crucible with a hardened and thickened inner wall, malachite powder was thoroughly mixed with a large amount of crushed charcoal. The charcoal was not only fuel, but also the key to providing a reducing agent (carbon) at high temperatures, reducing copper oxide (the main component of malachite) to elemental copper.
The small, specially designed vertical kiln was ignited. Wang Yan improved the blower equipment—a large air bag sewn from leather, which, when squeezed by wooden levers, could continuously blow air into the kiln, increasing the combustion temperature. This was much more efficient than simply relying on a pile of firewood. With the help of the blazing kiln fire and the continuously injected oxygen, the charcoal burned fiercely, and the temperature inside the kiln reached an unprecedented level.
The crucible was placed in the kiln core. Under high temperature, the malachite powder mixed with charcoal began to undergo a complex chemical reaction. Wang Yan and the craftsmen took turns operating the blowers, sweating profusely as they stood guard at the kiln opening, closely monitoring the situation inside through the observation holes. It was a long and arduous process, full of uncertainties.
After an unknown amount of time, when Wang Yan judged that the temperature was high enough, they carefully removed the crucible using specially made long-handled ceramic tongs. After it cooled slightly, they smashed the crucible open and found that the bottom contained some dark red metal particles of varying sizes and spongy copper chunks, along with a large amount of slag.
"It's done! It's copper!" Wang Yan picked up a piece of dark red copper that was still warm. Although it was rough, it was definitely metallic copper! He was overjoyed to have obtained metal on his first attempt at reduction. The craftsmen were also very excited. They had personally refined something they had never seen before from the "green Shitou"!
However, this was only crude copper, not very pure and containing impurities. They collected the crude copper particles they obtained, preparing to refine them a second or even third time to obtain purer copper. Meanwhile, another group began processing tin ore. Tin has a lower melting point and is relatively easy to smelt. They used a similar but gentler method to obtain crude tin, which they then refined.
Having obtained relatively pure copper and tin, the most crucial step is now—alloying them.
Bronze is a copper-tin alloy; different copper-tin ratios result in materials with varying hardness, toughness, and melting points. Wang Yan only knew the general range; the specific optimal ratio would require repeated experiments.
They started with the simplest tools. First, they set a copper-tin ratio (e. g., nine parts copper to one part tin), then placed the weighed copper and tin materials into a new small crucible and melted them in a kiln. The molten copper and molten tin fused together, and after cooling, they obtained an alloy ingot. Then, the craftsmen used Shichui and anvils to forge the alloy while it was still hot (or reheated), trying to make it into the prototype of a small hammer, an axe, or a short knife.
In the first few attempts, either the alloy was too brittle and cracked with a single tap, or too soft and lacked any hardness, or it had too many air bubbles during casting, resulting in a loose structure. Failures followed one after another, wasting a lot of precious metal materials.
But Wang Yan was not discouraged. He carefully recorded the proportions, temperature, and forging process each time, and observed the fractures and properties of the failed products. The craftsmen also accumulated experience in practice, and their mastery of the heat and forging force became more and more precise.
Finally, after trying several proportions, a ratio of approximately 90% copper and 10% tin showed satisfactory properties. Hammers forged from this alloy produced a clear, resonant sound when striking Shitou and were not easily deformed. Knives made from other proportions, once sharpened, could easily leave deep marks on Yingmu and even cut through softer stone. Axes made from other proportions, although still somewhat crude due to the primitive craftsmanship, possessed a sharpness and hardness far superior to Shifu!
When Wang Yan brought these rough but significant bronze artifacts—a small hammer, a short knife, and an axe—to Jianshi, neither of them showed any signs of fatigue.
"Father, look." Wang Yan handed over the items.
Jianshi took the small hammer with a puzzled look. It felt heavy in his hand, yellowish-green in color, and had a cool, metallic feel. He picked up a piece of flint he often used and tapped it gently with the hammer.
With a clear, crisp clang, a small piece of flint shattered, but the hammerhead remained completely undamaged.
Jianshi's eyes widened instantly. He picked up the short knife again and began slicing at the shaft of a Yingmu spear he carried. With almost no effort, wood chips flew everywhere, and a clear groove appeared on the spear shaft! He then tried the Shifu, and found it significantly more efficient and deeper in chopping wood than the Shifu.
"This... this is bronze?" Jianshi's voice trembled uncontrollably. He repeatedly stroked the cold metallic texture of the blade, then weighed the heavy axe in his hand, his eyes gleaming with astonishment. "Excellent! Excellent! Yan! Our Fire Tribe... has actually created bronze artifacts!"
He suddenly looked up, grabbed Wang Yan's shoulder with such force that Wang Yan staggered. "This is something even the Fish Tribe might not have, something the Valley Tribe treasures! And now our Fire Tribe can actually make it!"
After the initial euphoria came profound calm. The excitement on Jianshi's face was quickly replaced by a deep solemnity. He put down the bronze artifact, lowered his voice, and each word seemed to be squeezed out from between his teeth. "Yan, listen carefully. This matter is a hundred times more important than you inventing Ma'an and stirrups, or our refining of fine salt! This is the foundation that could make our tribe ten or a hundred times stronger, and it is also the root of our annihilation!"
He stared intently at his son. "From now on, the smelting and forging of bronze must be top secret! Those involved must be carefully selected and supervised to ensure no secrets are leaked! The bronze produced should not be used extensively for agricultural tools for the time being; priority should be given to manufacturing weapons! Spearheads, knives, axes! Arm our warriors! We must also try to make more sophisticated tools to prepare for building bigger and better ships for us!"
He paced back and forth, his thoughts becoming increasingly clear. "We have four thousand people now, which seems like a lot, but in the eyes of truly large tribes, it's not enough! With bronze, we finally have some confidence to protect ourselves and speak with authority! But this confidence is far from sufficient! Therefore, we must spare no expense to secretly and vigorously produce bronze! We must accumulate our resources!"
Wang Yan nodded emphatically. "I understand, Father. I will make the arrangements. We have found the appropriate ratio; the next step is to expand the scale, refine the process, and continue experimenting with other possible alloys. With the first batch of tools, our efficiency in mining and processing ore will also improve, creating a virtuous cycle."
"Good!" Jianshi slapped Wang Yan hard on the back. "Go for it! Just tell us what you need! The future of the Fire Tribe depends on this!"
In the darkness of night, in the most secluded corner of the Fire Tribe, the hearth fire was lit again, illuminating several focused and excited faces.