With the milestone now met, the miner said the shaft is ready to fit, and that will be done through this year. Shaft 2, at 10m (32.8 ft) in diameter, will be used for access, production and ventilation.

Chief executive officer Jeff Tygesen said the completion of sinking is the first of a number of key milestone leading to the production of ore from the Hugo North Lift 1.

When the operation reaches peak production levels around 2025, it will be the third largest copper mine in the world.

In related news, Turquoise Hill said the force majeure on Oyu Tolgoi’s concentrate deliveries remains in place. However, it confirmed that, despite the declaration earlier this month, there has been no disruption to goods and services arriving for the mine’s underground development.

Trucks, including its concentrate convoys, again started crossing the Ganqimaodu border zone on January 19.

Additionally, safe and normal operations have been maintained and there is no expected production impact, the company said.