XME•In other metals, LME aluminium CMAL3 slipped by 0.2% to $3,258 a ton in official activity while zinc CMZN3 and lead CMPB3 eased by 0.5% to $3,892 and $1,926 respectively. Nickel CMNI3 lost 0.2% to $16,595 and tin CMSN3 was steady at $54,200.
Copper prices fell on Wednesday under pressure from a stronger dollar and profit-taking after the metal tested technical resistance above $14,800 a metric ton.
Benchmark three-month copper CMCU3 on the London Metal Exchange (LME) was down 0.6% at $14,655 a ton in official open-outcry trading after touching $14,833 for its highest since the record high of $14,875 on September 10.
Comex copper HGc1 hit a record peak of $6.83 per lb, or $15,057 a ton, on Tuesday before retreating on Wednesday.
Comex copper inventories HG-STX-COMEX have started to record modest daily inflows as the premium on US copper futures over LME prices 0#LMECMXCU edged higher after a sharp pullback.
That pullback was triggered by a Reuters report that the White House had yet to decide on copper import tariffs that have raised concerns over affordability.
After months of heavy inflows, Comex warehouses now hold 69% of the roughly 1 million tons of copper tracked by global exchanges, supporting concerns about tightness outside the US.
The backdrop has helped LME copper prices to gain 18% this year and currently coincides with signs of robust demand in top consumer China ahead of public holidays on September 25 and October 1 to October 7.
Half of the 252,500 tons of copper stored in LME-registered warehouses MCUSTX-TOTAL, meanwhile, has been earmarked for delivery.
The impact of these supportive factors is evident in the spread between the LME cash copper contract and the three-month benchmark CMCU0-3, which swung to a premium this week.
The premium was last at $76 a ton, compared with a discount of $86 on September 14.
"Buyers are willing to pay a premium to secure metal sooner, reinforcing the narrative of a tighter market," analysts at RBC Capital Markets said.
On the supply side, traders were awaiting an update on contract negotiations with workers at BHP's Escondida copper mine.
