The benchmark S&P/ASX 200 index lost 20.1 points to 4,120.3 as of 2350 GMT.
New Zealand's benchmark NZX 50 index rose 0.8 percent to 3,240.7.
Top miners BHP Billiton and Rio Tinto both fell more than 1 percent, while Australia's biggest gold miner Newcrest Mining fell 2.4 percent.
The big four banks were down between 0.3 and 0.9 percent.
Sluggish Christmas sales depressed the retailers, with department store chain Myer Holdings down 1.7 percent, outdoor gear retailer Kathmandu down 1.1 percent, and JB Hi-Fi off 3.2 percent.
STOCKS ON THE MOVE
Murchison Metals jumped 3.5 percent to A$0.44 after Australia's Foreign Investment Review Board approved the sale of the company's stakes in an iron ore development and the Oakajee Port and Rail project to Japan's Mitsubishi Corp for A$325 million.
Beleaguered clean coal developer White Energy rose 2.6 percent after suing its partner Bayan Resources for damages, claiming the Indonesian firm had breached their joint venture by failing to supply coal to their clean coal plant.