US mining giant Newmount’s subsidiary PT Newmont Nusa Tenggara will operate the Batu Hijau mine in Indonesia until 2027.

Although the ore in the mine will run out by 2023, operations at the onsite processing mill will continue until 2027.

After this date, NNT plans to allocate $139m to close the mine and dismantle facilities, with full closure expected by 2033, according to The Jakarta Post.

The Batu Hijau mine started operations in 2000 and by the end of 2009 was estimated to have reserves of 11.47 billion pounds of copper, 11.57 million ounces of gold and 40.97 million ounces of silver.

The contract covers an area of 87,540ha and includes the Batu Hijau mine and several other potential mines on Sumbawa Island.

NNT plans to develop four mines on the island after 2017, including the Elang mine, which is thought to have a greater mineral potential than Batu Hijau.