Perth-based Portman, Australia's third largest iron ore producer, has delivered record earnings for its half due to higher prices for the commodity.

Portman booked a profit for the six months to June 30 of $137.1 million, 140 per cent higher than the same period in 2007, driven primarily by the increase in benchmark iron ore prices.

The price of iron ore has undergone six consecutive annual increases as its demand continues to be driven by the rapid urbanisation of China and other developing nations.

Second quarter earnings were 30.8 per cent higher than the same period in 2007 at $119.3 million.

Iron ore sales for the quarter were 13.6 per cent lower at 1.9 million tonnes due to restrictions related to railway line maintenance, which affected its Koolyanobbing project in WA.

Portman forecast total output for 2008 of eight million tonnes, comprising 7.7 million tonnes from Koolyanobbing and 300,000 tonnes from the Cockatoo Island project in WA.

Shares in the company gained 36 cents, or 2.01 per cent, to $18.31 at the close of trade. – Associated Press