Buried deep underground for 2500 years, the Yue King's sword has no rust, has the science explained clearly?

Ancient emperors or nobles would always bury many precious objects when they were buried, so in modern times, we often encounter some unique treasures in the cultural relics we unearth, such as swords, porcelain or jewelry.

Speaking of the sword, we have to mention the "world's first sword" unearthed in 1965 - the Yue Wang Gou Jian Sword, although this sword has been placed in the damp tomb for 2500 years, but it is very well preserved, almost no rust, which makes archaeologists who have seen countless treasures marvel, why is it preserved so perfectly? What casting process does it use?

The world's first sword- the Yue King's sword.

In December 1965, archaeologists found a bronze sword inserted in the scabbard of a black lacquered wood sword on the left hand side of the tomb owner's body in Wangshan, near Jingzhou City, Hubei Province, which looked very valuable.

This bronze sword is 55.7 cm long, the sword width is 4.6 cm, the hilt is 8.4 cm long, the total weight is 875 grams, and the sword body is covered with black diamond-shaped geometric dark patterns, engraved with clear "Qiwang Dove shallow, self-tutam" eight words, in the front of the sword grid is also made of blue glass, the reverse side is inlaid with turquoise into a fine pattern, the sword handle is also wrapped with silk rope, especially the inside of the sword head is also decorated with 11 concentric circles, and after research, this sword should be the Yue King's sword.

History records that at the end of the Spring and Autumn Period, the level of sword casting in the Wuyue region was very strong, and the Yue King's Gou Jian sword well reflected the highest level of short weapon manufacturing in that period, mainly in three aspects:

One is that it is buried in the damp soil after 2500 years almost no rust, to know that even with the stainless steel we make now, no one can guarantee that it will not rust after a thousand years;

The second is sharpness, when this sword is excavated, in order to test its sharpness, experts have experimented on it, stacked with more than two dozen pieces of A4 paper, and then took the sword to cross, and finally cut through 26 pieces of A4 paper.

Finally, the exquisite craftsmanship of the sword, take the 11 concentric circles, the interval is only 0.2 mm, the craftsmanship is very exquisite, and the overall layout of the sword is still very perfect, so the Gou Jian sword is known as the "world's first sword".

The secret of the sword's thousand-year-old stainlessness.

In order to find out the reason why the Gou Jian sword does not rust, experts first used a magnifying glass to observe the Gou Jian sword and then performed proton ray fluorescence analysis technology, and found that the composition of the sword was very complex, the main component was copper, and the copper content reached 80%-83%, followed by tin, with a tin content of 16%-17%.

Both elements are not easy to oxidize the elements, especially the main component copper, is an inactive metal, very difficult to corrode, in addition to containing a small amount of aluminum, nickel, iron and sulfur and other elements, and because of the different roles of the various parts of the sword, so the proportion of elements that make up each part is also different, such as the sword body contains more copper elements, and the blade tin content is relatively high.

In short, the composition of the whole sword is quite complex, the ratio of various elements is just right, such as the content of tin, the higher the general tin content, the greater the hardness, and when the tin content exceeds 20%, it will be more brittle, it is easy to break, but the tin content of this sword is just right, making the sword very sharp and not easy to break.

In addition, the sword was placed in the coffin, and it was protected by the sword scabbard, and the burial chamber was buried several meters underground, with almost no contact with the outside world, isolated from the air, so the sword was very well preserved.

In fact, when the Gou Jian sword was first found, it was not without rust at all, but it was very small, almost none, and now the Gou Jian sword has been corroded, and it is indeed not as good as the previous preservation in the tomb, which also shows that when the Gou Jian sword was unearthed, the main reason why there was almost no rust should be the problem of preserving the environment, after all, the closure of the tomb is indeed very good.

As for why the Gou Jian sword appeared in the tomb of the nobles of the Chu State, there are two theories, one is that the Yue King Gou Jian had a daughter who was married to the Chu State, and he may have taken this sword as a dowry and was brought to the Chu State with his daughter, and there is also a theory that when the Chu State attacked the Zhao State, he got the Gou Jian Sword and was later used as a funerary product.