The miner “is aware of speculation regarding a potential transaction involving Jiangxi Copper Co.,” First Quantum said in a statement. “The company confirms that discussions regarding a potential sale of a minority interest in First Quantum’s Zambian copper assets have occurred and are continuing. No transaction has been agreed upon and there is no guarantee that a transaction will be achieved.”

First Quantum became attractive to global miners after its market value had tumbled by almost half in the past five years. Last week, people familiar with the matter said First Quantum hasn’t yet received any formal takeover offers, but it has hired defense advisers to examine its options. The people asked not to be identified because the information is private.

Jiangxi Copper, China’s top producer of the metal, has built up a stake of less than 10% in First Quantum in recent months, according to people with knowledge of the matter.

First Quantum shares dropped as much as 12% to C$10.72 in Toronto trading before paring losses to C$10.88 at 10:35 a.m. The Canadian company posted the biggest two-day gain in more than three years on Friday.

First Quantum would likely best fit with Rio Tinto Group as the global miner seeks to diversify away from iron ore, a Liberum analyst said in a research note. Potential buyers may include several Chinese firms, National Bank analyst Shane Nagle, said in a note last week.

The list of potential buyers for the Canadian miner will likely be short because most diversified miners have exited Zambia, home to First Quantum’s Kansanshi mine, or show little interest in the area, Patrick Jones, an analyst at JPMorgan Chase & Co., said in a note last week.