PERTH - The Australian share market closed in the black on thin trading volumes amid a lack of key economic data and as the United States prepares for its Thanksgiving holiday on Thursday.

The benchmark S&P/ASX200 index was up 37.2 points, or 0.79 per cent, at 4,722.2 points, while the broader All Ordinaries index lifted 32.8 points, or 0.7 per cent, to 4,741 points.

On the Sydney Futures Exchange at 1618 AEDT, the December share price index contract was 26 points higher at 4,729 points, on volume of 21,861 contracts.

CMC Markets analyst David Taylor said the local market was directionless due to a lack of any substantial news or economic data, although Reserve Bank deputy governor Ric Battellino said Australia would benefit greatly from Chinese investment.

"If his views are correct, companies like BHP Billiton, Rio Tinto and Fortescue Metals should continue to drive the stock market higher," Mr Taylor said.

The major miners were mixed. BHP Billiton was up 96 cents, or 2.39 per cent, at $41.19 and fellow mining giant Rio Tinto slipped 19 cents to $71.70. Fortescue appreciated 12 cents, or 2.91 per cent, to $4.25.

The spot price of gold in Sydney at 1619 AEDT was US$1,177.10 per fine ounce, up US$10.00 on Tuesday's closing price of US$1,167.10.

"Gold continues to push to new highs but were seeing mixed performances from gold producers," Mr Taylor said.

"Essentially the market believes gold still has further to run, but investors are being cautious and choosing to take profits every once in a while."

Among gold mining stocks, Lihir inched one cent lower to $3.65, Newcrest retreated 22 cents to $36.98 and Newmont was six cents stronger at $5.80.

The big four banks were mixed. Commonwealth Bank was down 16 cents at $52.58, Westpac lifted 41 cents to $24.37 and ANZ rose 31 cents to $22.20.

National Australia Bank (NAB) said it was expanding its distribution across rural Australia through an alliance with Ruralco Holdings, offering seasonal finance and term loans to farmers.

NAB put on 44 cents to $28.43 and Ruralco was down one cent at $2.39.

Making headlines on Wednesday, grains handler and marketer GrainCorp expects lower grain receivals in Australia in its 2009/10 fiscal year as a result of continued drought.

GrainCorp shares were down seven cents at $6.29.

Programmed Maintenance Services has posted a five per cent fall in first half net profit but says it is in a strong position to expand its services.

Its shares fell two cents to $3.96.