COMEX copper prices mostly gained on Tuesday, with nearby contracts reaching a two-week peak, bolstered by speculative interest and Far Eastern buying in the face of a weak US dollar, dealers said.
COMEX active May futures ended at $1.3660 a lb, up 1.70 cents, after trading from $1.3480 to $1.3730.
The high was its loftiest level since March 3. Spot March gained the same to $1.3640 and the rest were 1.70 firmer to 1.20 lower.
Traders said a rally in copper on Monday prompted short covering that lifted prices nearer to resistance areas at above $1.37 a lb in New York and $3,000 a tonne in London.
Long liquidation by speculators last week had kept futures on the defensive, but buyers returned to the fore on Monday and Tuesday as futures appeared less overbought.
"It seems that last week's correction in copper is pretty much over, and we are now looking for copper to test and take out its recent highs," Man Financial analyst Ed Meir said in a report.
A soft dollar and warehouse stock declines propped prices as well, dealers said, while buying in Asia supported copper since Monday's firm close.
The US currency plunged against the yen on a report late Monday that Tokyo could halt selling yen for dollars by the end of March in order to boost Japanese exports.
The euro was flat against the dollar in the afternoon.
Overall, copper has been consolidating between roughly $1.25 and $1.38 after topping on March 2 at $140.30 which was its highest level in 8-1/4 years.
"We are very much stuck in a range. I think we need to break above $1.40 or down below $1.30 to get out of it," said one desk trader, referring to the May futures contract.
Final estimated COMEX copper volume hit 15,000 lots, higher than Monday's tally of 12,715. Open interest rose 1,262 to 76,897 contracts as of March 15.
At the London Metal Exchange, 3-months copper rose $64 to $2,994 a tonne with traders eyeing resistance at $3,000 and the recent 8-1/2 year peak at $3,055.