SYDNEY--Nathan Tinkler, the Australian electrician-turned-mining magnate who was forced to rapidly liquidate assets last year as coal prices slumped, has made a surprise return to the fold.

Mr. Tinkler's company, Bentley Resources, agreed to buy Peabody Energy Corp.'s (BTU) idled Wilkie Creek mine in Queensland state for US$70 million and the assumption of liabilities related to the mine's closure in December, the U.S. company said in a statement.

The liabilities included US$34.5 million in contractual obligations for the use of rail and port services and US$21.1 million for "asset retirement obligations," a St Louis-based spokesman for Peabody said.

A spokesman for Mr. Tinkler said the total purchase price, including all liabilities, was about 150 million Australian dollars (US$141 million).

Write to Ross Kelly at ross.kelly@wsj.com

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