At this price, the group is valued at about $59.2 billion and the flotation marks the biggest IPO so far this year.

Strong unofficial trading immediately pushed the market price up.

“Glencore’s offer has seen substantial interest from investors around the world and was significantly oversubscribed throughout the price range providing Glencore with a high quality, diverse and geographically spread investor base,” said Ivan Glasenberg, Glencore chief executive officer.

The company, based in Baar, set on Thursday the final price for the IPO at 530 pence, at the middle of the 480 to 580 pence range it announced early in May.

Conditional trading – unofficial trading of the shares on condition that they will eventually be fully listed on the stock market – began on Thursday on the London stock exchange, and the price jumped to 548 pence shortly after the market opened at 0700 GMT.

Full official trading in the shares will begin on May 24 in London and May 25 in Hong Kong.

Glencore, the world’s biggest commodities trader by revenue with $145 billion in 2010, has secured $3.1 billion from so-called cornerstone investors, who have subscribed to 31 percent of the shares on offer.

These investors include sovereign wealth funds in Singapore and Abu Dhabi, asset managers and private banks.

Glencore has said it would use funds raised by the listing to pay down debt, boost its stake in Kazzinc, a zinc producer with core operations in eastern Kazakhstan, and finance other projects to expand its business.

Ratings agency Moody’s said the move would improve the financial flexibility of the group to raise funds, as it gives it access to other forms of financing for future acquisitions.

The IPO comes as commodity prices soar amid huge demand from Asia, particularly China and India, for resources to power their economies.

Founded in April 1974 by trader Marc Rich, Glencore operated initially out of an apartment in central Switzerland’s Zug canton before quickly emerging as a major player in commodities trading.

From metals, minerals and crude oil, the group moved into agricultural goods and started to expand from simply trading third party commodities to acquiring ownership of resources in the late 1980s by purchasing its own mines.