Index ends third straight week of gains

Easing concerns about Europe's debt and further upbeat earnings from Wall Street boosted optimism.

The S&P/ASX 200 Index put on 24.8 points, or 0.6 per cent, to 4239.6.

For the week, the benchmark was up 1 per cent following a series of successful debt auctions in Europe that culminated in a sharp fall in yields on Spanish bonds on Thursday night.

Forecast-beating results from Wall Street banks Morgan Stanley and Bank of America buoyed hopes that the world's largest economy was on the track to recovery, adding to momentum in the Australian market.

"It's not that investors and markets have their heads in the sand but rather that the ratings downgrades and the news from the World Bank and IMF have already been factored in," said AMP Capital head of investment strategy Shane Oliver.

The day's biggest gainers were energy stocks, which rose 1.1 per cent. Woodside Petroleum rose 51? (1.5 per cent) to $33.99, AWE climbed 5.5? (4.2 per cent) to $1.38 and Beach Energy moved up 7? (5 per cent) to $1.475.

Resource stocks added 0.9 per cent in response to rising metals prices, strong production reports from the iron ore sector and reports of a rise in merger and acquisition activity among Brazil's miners.

Investors shrugged off data showing China's manufacturing sector contracted for the third straight month in January.

BHP Billiton firmed 14? to $37.48 and Rio Tinto rose 78?, or 1.8 per cent to $67.53.

Shares in Nexus Energy raced up to 29.5?, or 22 per cent, after they resumed trading. Nexus announced on Thursday it had reached a non-binding heads of agreement with Shell and Osaka Gas to develop an integrated oil and gas project at the Crux field off Western Australia.

The stock fell back to close at 25.5?, up just 1.5? or 6 per cent, as investors assessed the deal, which will see revenue from the Crux project pushed back as far as next decade.