Copper explorer Rex Resources will hand the development of Australia’s biggest fully permitted and shovel-ready copper project, Hillside on the Yorke Peninsula, to Indonesian group MACH.

In an offer valued at about A$393-million, MACH will acquire all the shares in Rex that it does not already own at A$0.47 apiece.

The news sent Rex’s stock soaring on the ASX to its highest level in about three years, hitting A$0.45 a share in Sydney on Monday.

The takeover offer price is a 179% premium to the price of the company’s most recent entitlement offer in January that was conducted at A$0.17 a share. It is also nearly double the company’s 90-day volume-weighted price (VWAP) of A$0.24 a share.

The transaction follows a competitive global partnering process that focused on securing A$854-million in funding for the Hillside copper/gold project.

“The transaction provides certainty of value and a significant premium representing a 98% uplift relative to Rex’s 90-day VWAP, as well as the opportunity for Rex shareholders to realise their investment at a ten-year historical share price high,” said CEO and MD Richard Laufmann.

He added that the transaction also represented a more certain outcome for wider stakeholders in Hillside, including the local community, the South Australian government and Rex employees who would benefit from the financial strength and track record of MACH to develop Hillside.

“Subject to approvals, we look forward to working with MACH through to completion and watching them develop the Hillside project, Australia’s largest fully permitted and shovel ready copper project,” said Laufmann.

According to the Rex website, Hillside contains a mineral resource of 1.9-million tonnes of copper and 1.5-million ounces of gold. In July 2020, the South Australian government approved Stage 1 of the project.

The capital expenditure for the development of the project is estimated to be A$854-million.

On average, Hillside is forecast to produce 151 500 t of copper concentrate, containing 42 000 t/y of copper and 30 500 oz/y of gold.