News: RIO Australian shares fall as miners drag, but eye third weekly gain

June 4 (Reuters) - Australian stocks declined on Friday as sliding commodity prices weighed on resource-heavy sectors, with a weaker finish on Wall Street overnight denting sentiment.

The benchmark S&P/ASX 200 index (xjo) fell 0.2% to 7,248.80 by 0026 GMT. For the week, however, it is up almost 1% and is set for its third straight weekly gain.

Mining stocks .AXMM , the biggest constituent of the benchmark, fell 2.2% as copper plunged to five-week lows. However, the subindex was headed for weekly gains of 0.6%.

Mining majors Rio Tinto (RIO) and BHP (BHP) shed 2.8% and 2%, respectively.

The gold index .AXGD led losses on the benchmark by declining 3.7% after spot prices slumped 2%. The sub-index has lost 3.8% so far this week.

Gold miner Northern Star (NST) shed nearly 5%, while Newscrest Mining (NCM) declined 3.1%.

Tech stocks .AXIJ eased 1.2%, tracking their peers on Wall Street, with index giant Afterpay Ltd (APT) falling 2.5%.

However, the energy index .AXEJ was up 0.3% as oil prices steadied after weekly U.S. crude stocks took a sharp fall.

The sub-index is set to gain 7.6% this week in its biggest weekly gain since Jan. 8.

Natural gas major Woodside Petroleum (WPL) added 0.4% on Friday, while Oil Search (OSH) gained 0.7%.

Banking stocks .AXFJ also rose 0.6% with the "big four" lenders trading higher.

Across the Tasman sea, New Zealand's benchmark NZX 50 index (nz50) was up 0.1% to 12,430, with Synlait Milk (SML) being the top gainer.

In other markets, Japan's Nikkei .N225 was down 0.9% at 28,798.07, while S&P 500 E-minis futures EScv1 were down 11.75, or 0.3%