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BEIJING/SHANGHAI, Dec 27 (Reuters) -
* China's leading copper smelter Tongling Nonferrous Metals Group has agreed with Freeport-McMoRan Inc for treatment and refining charges (TC/RCs) at $82.25 per tonne and 8.225 cents per pound as the 2018 benchmark, a company source with the smelter told Reuters on Wednesday.
* The term is 11 percent lower than the 2017 annual benchmarks of $92.50 per tonne and 9.2 cents per pound. The deal was done via video conference.
* "I can only say, this number reflects the market, it's a reasonable one," a company source said, declining to be named as he is not authorised to speak to the media.
* The benchmark has been agreed just days before the China Smelters Purchase Team that comprises 10 smelters holds a quarterly meeting to set the floor TC/RCs for the first quarter.
* Miners pay the TC/RCs to the smelters to process their ore and the level the sides agree to pay plays a large role in the profitability of the miners and the smelters. China is the world's largest consumer of copper. (Reporting by Tom Daly in BEIJING and Ruby Lian in SHANGHAI; Editing by Biju Dwarakanath)