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Feb 21 (Reuters) - Australian shares declined marginally on Tuesday, their third straight down day, as gains in basic material stocks were outweighed by losses in other sectors due to disappointing earnings.
The S&P/ASX 200 index closed down 0.07 percent, or 4.065 points, to 5,791.029
The basic material sector was driven higher by climbing copper and iron ore prices. Rio Tinto rose 2 percent while Fortescue Metals added 2.7 percent.
The world's largest miner by market capital, BHP Billiton declared a bigger-than-expected dividend and reported a near eight-fold rise in underlying net profit in half-year results announced after Tuesday's market close.
Shares of BHP, which fell the two previous days, rose 1 percent on Tuesday ahead of the financial results.
The energy sector was driven lower by slides in the share-prices for WorleyParsons, Oil Search and Duet Group.
WorleyParsons fell 7.8 percent, adding to losses on Monday after it reported a half-year statutory net loss of A$2.4 million.
Oil Search shed 2.1 percent after reporting a 70 percent slump in full-year core profit.
Duet Group shares dropped 1.8 percent.
Aconex Ltd shaved 6.2 percent after it posted a net loss of A$3.5 million for half year-ended Dec. 31, compared with profit of A$4.6 mln a year earlier. The stock was the second biggest loser on the benchmark.
New Zealand's benchmark S&P/NZX 50 index gained 0.23 percent, or 16.19 points to finish the session at 7,115.69.
Auckland International Airport and Fletcher Building both rose 1.5 percent.
Telecom company Spark New Zealand FELL 0.6 percent while a2 milk company lost 1.6 percent. (Reporting by Susan Mathew in Bengaluru; Editing by Richard Borsuk)