Big miners winners in lacklustre trading

The sharemarket closed slightly higher on Tuesday, boosted by gains from resource companies, following record production results from Rio Tinto.

At the close, the benchmark S&P/ASX 200 Index was up 4.9 points, or 0.1 per cent, to 4986.0. The broader All Ordinaries Index was up 3 points, or 0.06 per cent, to 4968.0.

Rio said it had increased iron ore production by 6 per cent to a record 127.2 million tonnes during the first half of the year.

The world's second-largest iron ore miner also shipped a record 118.6 million tonnes of the steel-making mineral, a 4 per cent lift.

Rio's shares closed 75¢, or 1.4 per cent, higher at $55.52. BHP Billiton finished 18¢, or 0.5 per cent, up at $33.43, but Fortescue Metals Group shares were flat at $3.50.

In other resource company activity, Paladin Energy's shares soared, with investors cheering the uranium miner's performance, notching up record production for the 2012-13 financial year. Paladin jumped 7¢, or 7.3 per cent, to $1.03.

Shares overall appeared to tread water in morning trade, as investors waited on the release of the Reserve Bank's July meeting minutes.

According to the central bank, another interest rate cut could be on the cards thanks to a benign inflation outlook.

CMC Markets sales trader Betty Lam said local trade was lacklustre ahead of the release of the minutes and fell away into the afternoon.

"Following China's trading pattern, local stocks generally wavered between mild gains and mild losses for most of the afternoon following the RBA's comment that 'economic activity continued to grow at a below-trend pace'," she said.

Beleaguered surfwear company Billabong is expected to announce asset sales and new loans within days as it fights to overcome weak revenue and oversized debt. Billabong went into a trading halt, last trading at 25¢.

Australia's biggest owner of natural gas pipelines, APA Group, has approached leading natural gas distributor Envestra about a merger proposal.

APA chairman Len Bleasel said the proposal would create Australia's largest energy infrastructure group, making it a top-40 listed company worth $6.6 billion.

APA shares finished 15¢ lower at $6.23, while Envestra gained 6.5¢ to $1.125.