Lubambe Copper Mines did not immediately respond to a request for comment.
The Zambia state firm, which owns the remaining 20% stake in Lubambe, said it will negotiate a new shareholders agreement and commercial terms with the Chinese company.
Lubambe, previously owned by African Rainbow Minerals and Vale SA, produced about 15,000 tons of copper last year but needs to raise output to about 2,500 tons a month to become sustainable, it says on its website.
JCHX said on its website it plans to “inject new vitality” into the copper mine, which is loss-making.
Some of the investment will go toward sinking a new shaft at Lubambe over the next two to five years which could help it access copper deposits below 1,000 meters, the mine’s CEO Wang Gang said on the Lubambe mine website.
(By Chris Mfula and Felix Njini; Editing by Jane Merriman)