UPDATE 1-Brazil's Vale raises less than hoped in share offering

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SAO PAULO, July 16 (Reuters) - Brazilian mining giant Vale RIO.N raised about 19.43 billion reais ($12.17 billion) in a global share offering on Wednesday, building up a war chest to help finance expansion plans and potential acquisitions.

The company, the world's largest producer and exporter of iron ore, said it priced 189,063,218 preferred shares (VALE5.SA) at 39.90 reais each and 256,926,766 voting shares (VALE3.SA) at 46.28 reais each.

Vale, formerly known as CVRD, went ahead with the offering despite a recent slump in financial markets that pushed its share price sharply lower.

When Vale first announced its plans for the offering on June 10, its preferred shares were trading at 48.62 reais and its voting shares at 58.40 reais. On Wednesday, the preferred shares closed 2 percent lower at 42.60 reais and the voting shares fell 1.42 percent to 49.20 reais.

Vale, one of the world's top diversified mining companies, has said it would use the proceeds from the sale to finance growth in existing businesses and future acquisitions, as stipulated in its current $59 billion investment plan.

Brazilian media and several mining analysts have speculated that Vale is gearing up for a big overseas takeover. Company executives, however, have denied they are in takeover talks.

Since Roger Agnelli took over as chief executive in 2001, Vale has completed 14 acquisitions, including the $18 billion takeover of Canadian nickel producer Inco in 2006.

Earlier this year, it tried and failed to acquire Swiss rival Xstrata (XTA.L) in a deal that some analysts valued as high as $90 billion, which would have made it one of the biggest takeovers in corporate history.

Vale's main shareholders -- the state-run pension fund Previ, the investment arm of Brazil's largest private-sector bank Bradesco (BBDC4.SA)(BBD.N), and Japanese trading house Mitsui & Co (8031.T) -- all said they would participate in the offering so their stake in Vale was not diluted.

($1=1.597 reais)

(Reporting by Daniela Machado, Writing by Todd Benson, editing by Phil Berlowitz)