Copper from Parys dominated world markets in the 1780s
A copper and zinc mine on Anglesey that has been dormant for more than 100 years is in the process of being bought by an Australian company.
Western Metals has agreed to pay around £14m for the Parys Mountain project, pending a feasibility review.
If the plan goes ahead, it will be the first mine of its kind brought into production in Britain in 30 years.
Before mining ended at Parys in the early 1900s, it yielded more than 300,000 tonnes of metal.
Bill Hooley, chief executive of Anglesey Mining, said negotiations with Western Metals began four weeks ago.
He said the companies would now enter into a period of "due diligence" - where details are checked, and after that it is expected a formal agreement will be signed.
A feasibility study is then proposed by the Australian company.
Mr Hooley said Anglesey Mining, which has been involved with the Parys Mountain site since 1984, is selling all its real estate rights, plus mining rights.
"From a company point of view it's good we have received this offer, it represents good value for Anglesey Mining and its shareholders. Also it's good news for Parys Mountain, it's a move forward," said Mr Hooley.
He said the company would continue to develop its Labrador iron ore project in Canada.
Local historian Bryan Hope said the copper mine on Parys Mountain was one of the most important in the world before work there ended.
Mr Hope said: "Mining goes back to the Bronze Age times and although there isn't much evidence of this, the Romans may have mined it."
He said it had been the most important local industry, with ancillary trades such as sulphur production and ship-building.
"Men, women and children worked the mine and there were women known as Copper Ladies who used to break up the ore into smaller pieces for smelting and grading."
Mr Hope, who is also secretary of Amlwch Industrial Heritage Trust, said the mining of copper could possibly lead to the regeneration of Amlwch port.
"It will be very interesting how they go about things and how they export the copper," he added.