UPDATE 1-Mechel postpones share issue, CEO buys stock

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MOSCOW, July 22 (Reuters) - Mechel (MTL.N), Russia's largest coking coal miner, has postponed until Aug. 11 a preferred share offering through which it plans to raise more than $2.5 billion, the company said in disclosure documents on Tuesday.

Mechel's billionaire chief executive and main shareholder, Igor Zyuzin, is also buying up 3 percent of the company's stock, a separate disclosure document showed, in a move analysts said was an attempt to drive up the miner's stock.

"The core shareholder's intention to buy 3 percent of Mechel's shares in the market may support the share price in the mid-term and is a vote of confidence for the fundamentals of the business," UralSib Financial Corp said in a note.

New York-listed Mechel, also Russia's sixth-largest steel producer, is planning to place 55 million preferred shares and has announced a price range of $50.50-$60.50 per share.

Market sources had said the offer book had been due to close this week and that some of the preferred shares were to trade in Frankfurt as Global Depositary Receipts. But sources familiar with the float said on Monday Mechel might cancel the offer or sharply reduce the price range.

One market source told Reuters the range, which implies a premium of up to 50 percent on the New York Stock Exchange price on Monday, was unacceptably high for investors but that Mechel was unlikely to accept less.

Mechel has so far declined comment.

Zyuzin, ranked Russia's joint 12th-richest man by Forbes magazine, is buying about 3 percent of Mechel stock on the open market through a Cypriot-registered company, Calridge Ltd, a U.S. regulatory filing showed.

UralSib said the purchase would take Zyuzin's stake in Mechel to nearly 73 percent. (Reporting by Robin Paxton and Polina Devitt; Editing by Louise Ireland and Erica Billingham)