"(Prices) will consolidate for the next few days," said a trader. "We've done a lot of work in terms of moving up."
The lower LME close meant the market might see more selling in Shanghai on Thursday.
Analysts had expected heavy buying by Chinese consumers returning from week-long holidays to drive prices up.
But Chinese traders sold copper on the LME that they had bought more cheaply on the Shanghai Futures Exchange before that market closed on Wednesday at its three percent daily limit up.
A firmer dollar supported by Federal Reserve Chairman Alan Greenspan's comment possibly signalling further rises in US interest rates undermined metals, prompting liquidation and profit-taking, Standard Bank analyst Robin Bhar said.
In prepared testimony to the Senate Banking Committee, Greenspan said the US economy was expanding at a healthy pace and that, despite rate hikes by the Fed, the real fed funds rate remained fairly low.
Greenspan will give the second part of this twice-yearly testimony on Thursday.
The euro fell to $1.2968, down 0.4 percent from late Tuesday's levels and more than a cent down from its session high. Man Financial analyst Edward Meir said in a note: "Copper and aluminium both look constructive and are still not yet overbought technically.
"However, we are leery about a relatively oversold US dollar, rising copper stocks, slumping Japanese and EU growth rates and continued light volume.
"Many are looking for a sustained push through the $3,180 resistance in copper and $1,880 on aluminium to precede a re-test of the old highs. While the charts may in fact be pointing to that possibility, the fundamentals don't."
Mining shares gained on Wednesday as BHP Billiton more than doubled first-half profit on demand for metals led by China, despite a decline in Britain's FTSE 100 index.
BHP Billiton was the top blue chip gainer, up 3.5 percent as the world's biggest miner announced the forecast-beating results and said demand would outstrip supply for many commodities over 2005, after which it would back off.
Aluminium rose $6 at $1,876 after briefly nearing $1,890.
Strength returned to zinc after the market tested lower on light profit-taking. The metal ended up $5 at $1,333, while lead fell $10 to $906.
Nickel was $200 lower at $15,400. Tin was $100 down at $7,825.