Folded Steel in China: From Han-Dynasty Refinings to Longquan Pattern Steel
Short answer: Folding and re-forging steel is not only a Japanese or Middle Eastern idea. In the Han dynasty, Chinese smiths were already grading blade steel by how many times it had been refined: 30, 50 or 100 refinings. Today's Longquan workshops continue that forging tradition, which China listed as national intangible cultural heritage in 2006. On a modern listing, pattern steel or Damascus means layers of different steels forge-welded together so that a visible pattern appears after etching.
Key takeaways
- Han-dynasty dao (single-edged swords) were made from steel described as 30-fold, 50-fold and 100-fold refined.
- A Han steel sword in the Xuzhou Museum carries an inscription recording its forging process as well as its date and maker.
- Longquan sword forging was listed in China's first batch of national intangible cultural heritage in 2006 (item Ⅷ-37).
- Modern pattern steel uses layered steels for looks; refining was about cleaning and evening out the metal. They share the same forge-and-fold roots.
Refining: what folding was originally for
Early iron and steel were full of slag and uneven in carbon. Heating a bar, hammering it out, folding it and welding it back together squeezed out impurities and evened out the metal. Each cycle was a refining. In a 2023 study that reconstructed a Han-dynasty ring-pommel dao using ancient methods, historian Hu Xiaojun notes that Han metalworkers made dao from steel labelled sanshilian, wushilian and bailian: 30-fold, 50-fold and 100-fold refined. Ring-pommel dao from the Mancheng tomb and the Dabaotai tomb in Beijing were made from this type of steel.
Smiths were proud enough of this work to write it on the blade. The Xuzhou Museum holds an Eastern Han steel sword from a Han tomb at Caoshan, about 109 cm long, known as the fifty-refinings sword. According to the museum, its inscription records the date, place of manufacture, workshop, craftsman and forging process.
Longquan: 2,500 years of sword making
Longquan in Zhejiang is linked by legend to the swordsmith Ou Yezi, and the town's name comes from one of his swords, Longyuan. You can read the full story in Longquan: The Town That Has Made Swords for 2,500 Years.
In 2006 China's State Council placed Longquan sword forging (龙泉宝剑锻制技艺) in its first list of national intangible cultural heritage, as traditional craft item Ⅷ-37. The official listing notes the local iron ore, whetstones, hardwood for scabbards and mountain spring water for quenching. It also records a traditional saying about how much material forging consumes: three jin of raw iron for half a jin of steel. Most of the metal is lost as slag and scale on the way to a finished blade. The listing also warns that mass production and profit-driven shortcuts have put the traditional craft at risk, which is why it is protected.
From refined steel to pattern steel
Refining used one steel and aimed for an even, clean result. Pattern steel deliberately combines two or more steels with different carbon or nickel content. After forging, the blade is etched in acid and the layers react differently, showing light and dark lines. Twisting, cutting or stacking the layers creates patterns such as waves, feathers or rings. The forging skills are the same family; the goal is different.
How these terms appear on LQ Forge listings
| Listing says | What you are getting |
|---|---|
| Pattern steel / pattern-welded steel | Layered steel forged and folded; the pattern shows after etching |
| Damascus pattern steel, or Damascus with a named pattern (twist, ladder, feather) | Modern pattern-welded steel, not historic wootz crucible steel |
| Self-forged laminated steel | Steel made in the workshop and laminated, so the edge and body are different steels |
| T10, 1065, 1095, 65Mn | A single steel, not pattern-welded, even if the blade is clay-tempered |
For how each steel performs, see our sword steel guide. Browse pattern steel blades in our katana and Tang dao collections.
Frequently asked questions
Does more folding always mean a better blade?
No. Folding removes impurities from uneven early steel. Modern steel is already clean, so extra folds mainly add pattern. Heat treatment matters more for performance.
Is Chinese pattern steel the same as Damascus?
In modern usage, yes: both mean layered, pattern-welded steel. Historic Damascus was a different crucible steel from the Middle East and India.
Are Longquan swords still hand forged?
Many workshops still hand forge, especially for higher grades, while others use machine hammers for parts of the process. Each LQ Forge listing states the steel and construction so you can see what you are buying.
Does pattern steel need special care?
Yes, if it is made from carbon steels, which most are. Wipe and oil it like any carbon blade; see our sword care guide.
Sources
- Hu Xiaojun, "Rediscovering Ancient China's Sword-Making Techniques: Insights from Reconstructing a Han-Dynasty Ring-Pommel Dao", in Martial Culture and Historical Martial Arts in Europe and Asia (Springer, 2023). doi:10.1007/978-981-19-2037-0_7.
- Xuzhou Museum, Fifty-refinings steel sword, Eastern Han dynasty.
- China Intangible Cultural Heritage Network, 龙泉宝剑锻制技艺 (Longquan sword forging), item Ⅷ-37, 2006.
