British broadsheet the Financial Times quoted unnamed sources as saying that Vale is in discussions to sell a 10-15% stake in the unit, in a move aimed at boosting its nickel and copper output amid rising demand driven by the global energy transition.
Bankers value the entire metals unit at around US$25 billion, according to the Financial Times.
The news follows Vale last week announced that it is transferring its nickel and copper assets into separate entities.
Vale says it is the world's largest producer of nickel.
World nickel consumption is forecast by Australia's office of the chief economist to rise from 2.77 million tonnes in 2021 to 3.14 million t by 2024.
Copper consumption over that same time period is forecast to grow from 25.25 million t to 27.3 million t, it said.
Vale estimates that its 2024-2026 nickel production will average 230,000t per year before rising to above 300,000tpy after 2028.
The company expects its copper production to average 390,000-420,000 tpy from 2024-2026 and to climb to roughly 900,000tpy beyond 2028.
Goldman Sachs has been hired by Vale to advise on any possible transaction, according to the Financial Times.
"No decision has been made regarding any specific transaction and we will keep the market updated accordingly," Vale said.
Vale's share price traded up 1% day on day at US$14.80 on 5 October.
