Updates official prices

By Julian Luk

London Oct 4 (Reuters) -Copper prices were on track for weekly losses on Friday as momentum slowed after stimulus measures from top consumer China sent prices to four-month highs earlier this week.

Three-month copper on the London Metal Exchange (LME) CMCU3 rose 0.7% to $9,934 per metric ton during official rings.

It was still 0.4% lower on a weekly basis, on track for the first decline in four weeks as the market awaits cues on how China's stimulus could transform into meaningful support for metals including grid investments and credit support for heavy industries.

Traders also eyed opportunities arising from gaps between copper prices across commodity exchanges.

LME copper has gained 10.8% in the past month, but still lags a rally at its rival Chicago Mercantile Exchange (Comex). Its most traded front-month copper contract HGc1 rose 11.7% to $4.5045 per lb during the same period.

The gap, if it continues to grow, could prompt more copper shipments to the U.S. in the coming months, a trader source said.

Comex copper inventories have already grown 66% since the start of September to 66,610 tonnes. 0#HG-STOCK

Meanwhile, the Shanghai Futures Exchange (ShFE), the metals trading platform for the biggest physical market in China, will resume trading next Tuesday. The focus is on how commodity prices will catch up with reactions to stimulus plans.

For other metals, aluminium CMAL3 increased 1.4% to $2,665 and nickel CMNI3 climbed 1.3% to $17,825. LME zinc CMZN3 advanced 1.4% to $3,167.5, lead CMPB3 was up 0.5% at $2,153.50, while tin CMSN3 was up 0.1% at $33,750.

Reporting by Julian Luk in London; editing by David Evans and Shreya Biswas

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