TORONTO (miningweekly.com) – Shares in First Quantum Minerals fell almost 12% in Toronto on Tuesday, after the Supreme Court in the Democratic Republic of Congo ruled that some rights for  two of the company's mines were awarded illegally.

Rights awarded for the Lonshi and Frontier copper  should revert to government-owned company Sodimico, the court said.

First Quantum announced the news on Monday, but the TSX was closed for a Canadian holiday.

Last September, the DRC government ordered the Kolwezi tailings project, in which First Quantum owns 65%, closed.

The company, together with partners the International Finance Corporation and South Africa's Industrial Development Corporation said in February that international arbitration proceedings had been launched against the government of the DRC and its mining company, Gécamines, which also has a minority stake in the project.

The Lonshi and Frontier rights were revoked in “retaliation” to the arbitration, First Quantum CEO Phillip Pascall told analysts on Monday.

Shares in First Quantum fell 11,83% on Tuesday, to C$55,36 a share by 16:10 in Toronto.

The stock traded as low as C$51,80 a share earlier in the day.

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