China"s copper imports in November rose 24.3% from the previous month to their highest since March at 510,402 tonnes, customs data showed on Tuesday, as demand increased after the easing of a power crunch that had dented industrial production. Arrivals of unwrought copper and products in the world"s top consumer of copper were still down 9.1% year-on-year, however, despite rising for a third straight month in November, the General Administration of Customs said. Activity in China"s copper-intensive manufacturing and construction industries picked up in November as widespread power rationing and a surge in prices of raw material eased. read more Refined copper stocks in Shanghai bonded warehouses fell 17% in November to stand at just under 170,000 tonnes, a record low. However last month customs told companies, including copper importers, that it would temporarily stop issuing value-added tax (VAT) invoices as it looked to defer some tax revenue into 2022, potentially discouraging purchases. read more Arrivals of copper concentrate, or partially processed ore, hit a record high of 2.19 million tonnes in November, up 21.9% month-on-month. "Easing power shortages and favourable treatment charges encouraged more concentrate buying," ANZ analysts wrote in a note. The higher purchases also reflected lower smelter maintenance in November than in previous months, said CRU analyst Craig Lang. Copper miners in talks with smelters on 2022 contracts are closely watching China"s concentrate imports, with a looming shutdown of the Las Bambas mine in Peru set to hit supply. read more ALUMINIUM China"s exports of unwrought aluminium and products rose 20.1% year-on-year to 509,318.50 tonnes in November, the highest since March 2020. "The risk of shortages of magnesium... during August-October has forced many semis plants outside China, predominantly in Europe, to reduce or suspend orders for magnesium-intensive aluminium alloys," said Wood Mackenzie analyst Kamil Wlazly. Despite easing magnesium supply risk, Chinese semis exports will increase in the next few months "as buyers receive orders made as a hedge against potential supply disruption from the shortage of magnesium," Wlazly added. read more The European Commission"s decision to delay a 14-25% import duty for sheet and coil product from China could also boost exports. "We expect significant volumes of standard sheet products to be heading for the EU market from China over the coming months as distributors take advantage of the delay." Reporting by Tom Daly; Additional reporting by Eileen Soreng and Mai Nguyen; Editing by Clarence Fernandez and Jan Harvey Our Standards: The Thomson Reuters Trust Principles.