In 1965, archaeologists discovered 50 ancient tombs while carrying out a survey in Hubei Province, just 4 miles (7 kilometers) from the ruins of Jinan, capital of the ancient Chu State. During the excavations of the tombs, researchers unearthed the sword of Goujian alongside approximately 2,000 other artifacts. The Sword of Goujian is one of the earliest known Jian swords, a double-edged straight sword. Jian swords are among the earliest sword types in China and are closely associated with Chinese mythology. Forged of copper and tin, it is renowned for its unusual sharpness and resistance to tarnish rarely seen in artifacts so old. This historical artifact of ancient China is currently in the possession of the Hubei Provincial Museum.
The sword is 55.7 centimeters long with a 4.6-centimeter-wide blade and 8.4-centimeter-long handle. On one side of the blade, two columns of text are visible. Eight characters are written in an ancient script which was found to be one known as Bird-worm seal script (literally "birds and worms characters" owing to the intricate decorations of the defining strokes), a variant of seal script. Initial analysis of the text deciphered six of the characters, "King of Yue" and "made this sword for [his] personal use". The remaining two characters were probably the name of this King of Yue.
In the 1990s, other research has revealed a high proportion of sulfur around the flower pattern and sulfide cuprum, which is rustproof. On the blade's surface scientists have also found traces of a chemical treatment used to prevent rust.
Sources:
http://www.chinaculture.org/gb/en_curiosity/2004-06/23/content_47488_2.htm
https://en.wikipedia.org/wiki/Sword_of_Goujian
http://www.theepochtimes.com/n3/1704453-goujian-the-ancient-chinese-sword-that-defied-time/
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