Falls by heavyweight iron ore miners and the tech sector dragged the ASX 200 index down 0.4 per cent to 7780.20 points.
The big iron ore miners turned lower as iron ore futures fell 2.5 per cent in Singapore, amid ongoing concerns over Chinese demand. BHP dropped 0.6 per cent to $43.62, Fortescue fell 1.2 per cent to $25.20 and Rio Tinto declined 0.2 per cent to $121.41.
The ASX declines followed a weak lead from Wall Street, where tech stocks led the declines and the S&P 500 fell 0.3 per cent. Tech stocks were also leading declines on the ASX, with WiseTech losing 2.3 per cent to $94.29 and Xero down 2.7 per cent to $133.39.
The heavyweight banking sector was weaker as CBA dipped 0.2 per cent to $118.60, NAB fell 0.3 per cent to $34.46, Westpac dropped 0.8 per cent to $26.24 and ANZ eased 0.3 per cent to $29.06. But Macquarie lifted 0.5 per cent to $198.49.
Mesoblast surged as much as 58 per cent before closing more than 45 per cent higher at 48c, as the biotech gears up for a third attempt to gain US FDA approval for its lead product candidate.
Copper producer 29Metals tumbled as much as 36 per cent before ending down 26 per cent at 40c after suspending operations at its Queensland mine due to further heavy rainfall events.
Energy stocks tracked higher oil prices overnight with Woodside rising 1 per cent to $30.37, Santos gaining 0.4 per cent to $7.61 and Viva Energy hitting a record high, up 1.6 per cent to $3.72.
Shares in billionaire retailer Solomon Lew's Premier Investments lifted 4.4 per cent to $32.00 on the back of its demerger plans and better-than-expected earnings result.
The Stokes-controlled Seven Group fell 4.1 per cent to $39.62 after it warned Boral, which rejected its takeover offer, about 'misleading' investors. Boral dropped 2 per cent to $6.03.