Shares in the big mining companies fell sharply after commodity prices tumbled overnight.
A short time ago, BHP was down 4.6% to $17.56 and Rio Tinto 4.3% to $44.72.
BHP, the world’s biggest miner, has lost 10% of its share price in just a week.
The rest of the market was being dragged down today by resources stocks. The ASX 200 was at 5,291.80, down 28.90 points or 0.54%.
The Australian dollar was also under pressure, hitting a session low of .7302 against its US counterpart.
And Fortescue Metals dropped 6.25% to $2.85 as iron ore prices dropped 3.8% to $US55.60 a tonne.
Energy stocks also slipped following a 3.9% fall overnight in the price of iron ore.
Woodside Petroleum had lost 2.3% to $26.70 and Santos was down 4% to $4.01.