Lundin Mining Corp. has further extended the period to exercise its right of first offer for Freeport-McMoRan Inc.'s indirect stake in TF Holdings Ltd., which controls an 80% interest in the Tenke Fungurume copper-cobalt mine in the Democratic Republic of the Congo, until Oct. 20.

Freeport confirmed the sale of its 70% interest in TF Holdings to China Molybdenum Co. Ltd. in May, for US$2.65 billion in cash and up to US$120 million in contingent consideration.

According to a Sept. 28 report by Mining.com, Lundin Mining's previous extension could indicate a bigger deal in the making involving China Molybdenum and the DRC's state-owned Gecamines SARL, which has a 20% direct ownership in the project, and opposed the deal earlier this week.

Lundin Mining, which holds a 24% interest in Tenke Fungurume, booked a US$772 million impairment on its stake in the property for the second quarter.

Should Lundin Mining work up a deal on the same terms as laid out in the Freeport-China Molybdenum agreement, its interest in the project could be valued at about US$1.2 billion.

The new deal may result in Lundin Mining becoming a major shareholder together with China Molybdenum and Gecamines.