Named after the Isle of Man headland, Bradda Head was co-founded by Mr Mellon, who owns about 20pc of the company, in 2017. The company struck up a joint venture deal with the Australian-listed Zenith Minerals for an interest in Zenith’s lithium projects.
In February Zenith sold its stake in the US lithium assets to Bradda for $250,000 (£180,000) and a 15pc interest in Bradda, to focus on gold.
Bradda had intended to sell 29pc of its shares at 5.5p apiece but the offer has been oversubscribed ahead of the listing and it is selling 39pc, raising more than £6m. It will use the money for development work.
Mr Mellon is known for his investments in science, but made much of his fortune in property and mining.
He co-founded lithium and uranium miner UraMin in 2005, floating it on AIM before it was bought by Areva for €1.8bn (£1.6bn). He remains a non-executive director at Bradda, which is chaired by Ian Stalker, who was chief executive of UraMin before its sale. He plans to keep hold of his stake following the float.
US president Joe Biden and other Western leaders are keen to cut China’s dominance in the supply and processing of lithium and other key battery metals. The administration is also keen to promote lithium mining in the US to help create jobs, as long as it is responsibly done.
Lithium prices on the spot market have risen to above $12,000 a tonne, more than double the levels in November last year, according to Benchmark Mineral Intelligence (BMI), which forecasts acute deficits from 2022.