Gold mining company Sibanye-Stillwater has agreed to acquire a 19.99% stake in New Century Resources for $46m, expanding its tailings retreatment exposure in Australia.

The investment will be made through a subscription for newly issued New Century ordinary shares by Sibanye-Stillwater for a maximum cash consideration of $46m.

Tailings management and rehabilitation company New Century Resources currently owns the Century tailings zinc retreatment operations in Queensland, Australia.

In 2016, Century’s operations were placed on care and maintenance following 16 years of production. This was due to the depletion of the original open-pit reserves.

New Century converted existing processing infrastructure and completed an infrastructure overhaul in August 2018.

Since then, the Century project has been re-processing tailings.

Sibanye CEO Neal Froneman said: “This investment in New Century represents a significant next step in our strategy of building a leading global tailings retreatment business, diversified by commodity and geography, and is aligned with our sustainability strategy of building a climate change resilient business.”

Sibanye expects the investment in New Century to complement its existing investment in DRDGold, a South African gold tailings retreatment company.

The transaction is anticipated to close by the end of this tear.

Meanwhile, New Century agreed to acquire the Mt Lyell copper mine in Tasmania from Monte Cello BV (MCBV), a unit of India’s Vedanta, via an option agreement.

According to estimates, the Mt Lyell mine holds mineral resources of about 1.1Mt of ‘green’ copper and about 1Moz of gold.

In a separate announcement, it was said that Sibanye-Stillwater and Australian lithium supplier Ioneer are set to begin production at the Rhyolite Ridge Lithium-Boron Project in the US.

The move comes as Sibanye-Stillwater completed a $70m investment in Ioneer through a share placement.

This follows the signing of a deal by the two parties last month whereby the South African miner agreed to purchase a 50% stake in the Ioneer project for $490m.