Chinese paktong (copper-nickel-zinc alloy)
Alpaca china (paktong, cobre-níquel-cinc)
- Date
- c. 350 (mención) / century XVIII (exportación) · confidence low
- Place
- Huize, Qujing, Yunnan, China
- Credited to
- Yunnan metallurgists
- Field
- Matter & energy
⚠️ Disputed: the sources disagree.
What it is
A white alloy of copper, nickel and zinc, resembling silver and rust-resistant, known in Yunnan since antiquity and exported to Europe in the 18th century. Its imitation gave rise to German silver (nickel silver) in 1823.
'White copper' (baitong) already appears in the Huayang guozhi (c. 350); Bactrian cupronickel coins (2nd century BCE) may have used metal of Chinese origin, though this is debated.
What it led to
- German silver, or industrial nickel silver
- analyses that confirmed nickel as an element