TOKYO, Sept 18 (Reuters) - The tsunami that hit the Chilean port of Coquimbo after this week's earthquake in the central part of the country flooded a warehouse for copper concentrate from the Caserones mine, a spokesman of Japan's JX Nippon Mining & Metals said on Friday.
The Japanese mining company does not currently know how much copper concentrate was being held at the warehouse or how the supplies were affected, the spokesman said.
"It's our basic policy not to keep much inventory (at the warehouse), but stock levels change depending on shipping schedules," he said.
A source at a trading house in Singapore said that any damage to the stockpile at the port is unlikely to affect the market balance, because most smelters have a pipeline of supplies that is well stocked to December-January.
Analysts still see a small surplus for copper this year.
An earthquake of magnitude 8.3 hit central Chile on Wednesday, killing 11 people and sending giant waves crashing into coastal areas. Waves of up to 4.5 meters (15 feet) slammed into the port city Coquimbo, which the government declared an emergency area.
Caserones, which began commercial operation in May 2014, produced 19,000 tonnes of copper concentrate last year and 18,000 tonnes in the January-June half of this year.
JX Nippon Mining & Metals, a unit of Japan's JX Holdings Inc and Japan's biggest copper smelter, still plans to bring the Caserones mine to full operation in September at output of 150,000 tonnes a year, the spokesman said.
Supply concerns have been shunted back into the limelight for the copper market, after the quake in Chile sent prices to two-month highs.
While no major impact was recorded by any of the major miners, some such as Glencore have announced production cuts, as prices that have festered near six-year lows make some operations unprofitable. (Reporting by Yuka Obayashi; Additional reporting by Melanie Burton in MELBOURNE; Editing by Tom Hogue)