Copper prices leapt to three-and-a-half-year peaks on Wednesday after a jump in China’s imports of the metal in November boosted expectations of stronger demand from the top consumer.

Benchmark copper on the London Metal Exchange was up 0.9 percent at $7,190 a tonne by 0955 GMT from an earlier $7,210, its highest since July 2014.

Prices of the metal used widely in power and construction are up more than 10 percent in December and nearly 30 percent in the year to date.

“China’s trade data lit the fire under copper. Sentiment is very bullish,” one copper trader said, adding that if volumes tail away there could be some volatility.

IMPORTS: China’s copper imports rose to 329,168 tonnes in November, up 19 percent year on year. Over the first 11 months of 2017, however, copper imports of 2.915 million tonnes are down more than 10 percent from the same period in 2016.

JIANGXI: Traders said a media report, later denied, that China’s top copper producer, state-owned Jiangxi Copper, had stopped production also supported prices this week.

SMELTER: Pan Pacific Copper, Japan’s biggest copper smelter, expects copper prices to rise by more than a quarter over the next two years as global demand grows and outpaces supply.

TECHNICALS: Copper prices face resistance at $7,212, the high from July 2014, followed by $7,220 from February 2014 and $7,254 a Fibonacci retracement level on the monthly chart.

ALUMINIUM: Prices rose 0.5 percent to an eight-week high at $2,204.5 a tonne.

CAPACITY AND INVENTORIES: Bullish sentiment in the aluminium market was reinforced by news that China’s government has criticised officials in the industrialised province of Shandong for deceiving authorities to evade capacity cuts in the polluting coal, steel, aluminium and chemical sectors.

However, aluminium stocks in warehouses AL-STX-SGH monitored by the Shanghai Futures Exchange, at a record 741,324 tonnes, suggest surpluses in China, the world’s largest producer and consumer of the metal.

OTHER METALS: Zinc gained 0.3 percent to $3,274 a tonne, lead added 0.7 percent to $2,508, tin was up 0.6 percent at $19,645 and nickel slid 1.4 percent to $11,960.