The most-traded June copper contract on the Shanghai Futures Exchange jumped as much as 3.5% to 72,820 yuan ($11,230.38) a tonne, a level unseen since February 2011. It closed up 3% at 72,480 yuan a tonne.
Three-month copper on the London Metal Exchange hit $9,965 a tonne, its highest since March 2011, before retreating to $9,921 a tonne by 0705 GMT, still up 1.7%.
Copper is often used as a gauge for global economic health and is used in electric vehicles and renewable energy productions.
Mining unions and port workers in Chile have threatened to protest over pension savings withdrawal issues.
Copper prices are being supported by strike threats in Chile, though high prices are deterring downstream physical market from buying, ING analysts said in a note.
FUNDAMENTALS
Yangshan copper premium
One party controls 80%-90% of available copper stocks and short-term futures on the LME, exchange data showed.
Spot copper treatment charges (TCs) in China
ING said it is “possibly an early sign that spot TCs may be bottoming, but still too early to call”.
ShFE zinc prices soared 3.2% to 22,430 yuan a tonne, their highest since March 23, and ShFE nickel ended up 3.6% at 126,560 yuan a tonne. Aluminium hit a more than 11-year high at 18,655 yuan a tonne.
LME aluminium hit a three-year high of $2,412 a tonne and nickel rose 1.7% to $16,955 a tonne.