Zijin Mining Group Co has dropped a plan to acquire a Congolese copper miner, the second time this year it withdrew from an overseas investment plan.

An agreement to acquire Platmin Congo Ltd expired on August 31 as the company failed to complete the purchase, Zijin, China's largest gold producer, said in a statement to the Shanghai Stock Exchange yesterday.

Zijin and the China-Africa Development Fund in May offered to buy Platmin for US$284 million to gain copper and cobalt assets.

Zijin said the parties failed to reach a deal on further extension of the agreement and didn't give a reason.