Masoud Alikhani, chairman of the Zambia-focused zinc and lead processor Berkeley Mineral Resources, has substantially lifted his stake in the firm, spending £20,000.
Alikhani, a former chairman of Cape Diamonds, which mines for the gemstones in South Africa, bought 2m shares at a penny a time and now has just less than 5.4m.
Shares in the company soared after it made the announcement of the purchase.
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They had already posted strong gains last week when the firm said it was close to securing the right to process waste from a dump at the Kabwe zinc and lead mine in Zambia.
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