Copper prices gained on Tuesday for a third straight session, lifted by optimism over economic recovery in top metals consumer China and by a weaker dollar.

China’s economic data released this month points to signs of improvement, including rising auto sales and rebounding factory activity.

“China’s old economy of manufacturing and industry is motoring along and that’s good for metals. We also saw strong Chinese imports of copper in July. So I think those indicators are the reason why investors are continuing to buy the dips,” said independent consultant Robin Bhar. “The metals also seem to be keeping lock step with the stock markets, which in turn are taking their cue from the massive fiscal and monetary stimulus, which is ongoing.”

Three-month copper on the London Metal Exchange was up 0.7% at $6,493.50 a tonne by 0950 GMT. The most-traded September copper contract on the Shanghai Futures Exchange closed up 0.9% at 50,830 yuan ($7,337.42) a tonne.

The U.S. dollar hovered near two-year lows, making dollar-priced LME metals cheaper to buyers using other currencies.

* LME zinc and lead stocks extended their gains on Tuesday after more inflows to warehouses, both hitting their highest levels since September 2018. Inventories of each metal, which are often found in the same ore bodies, have nearly doubled over the past month, partly due to weak demand during the pandemic.

* Nickel ore at 14 Chinese ports edged up to 7.99 million tonnes as of Aug. 7, the highest since June 28, research house Antaike data showed.

* LME nickel climbed 0.8% to a near-nine month peak of $14,715.

* Nickel pig iron prices in Inner Mongolia with 10%-15% nickel content rose to a seven-week high of 1,030 yuan a tonne, Antaike data showed.

* LME zinc advanced 1% to a nine-month high of $2,467 a tonne, while aluminium rose 1% to $1,774.

* Lead added 0.4% to $1,978 after hitting $1,982, the strongest in nearly seven months, and tin gained 0.6% to $17,420.