The red metal fell 4.4% to US$6374.75 per tonne, the lowest since mid-August.
Despite China going on holiday today, there could be some recovery in copper on Friday after reports of a possible strike at Escondida.
Zinc was down 3.3%, while nickel, tin, lead and aluminium all fell by over 1%.
"Things have been pretty good for metals and bulk commodity prices over the past few months, with many recovering to trade above pre-COVID levels as competition for units increases amid sequential demand improvement," BMO Capital Markets said this week.
"However, after such a run we are now at the time of the cycle to consider how long the duration of prices trading at levels to incentivise supply back to the market is needed.
"Moreover, in our view, the impact of China's strong fiscal influence on reflating prices is now behind us, and overall global economic and geopolitical risks remain high."
Gold rebounded, rising as high as $1917.90 an ounce, but last trading at $1913/oz.
Due to a technical issue, our commodities table is unavailable today.