The price of iron ore has again failed to find support in overnight trade, slipping further away from the $US85 a tonne mark.

Benchmark iron ore for immediate delivery to the port of Tianjin in China is currently trading at $US83.20 a tonne, down half a per cent from its $US83.60 closing mark in the previous session.

The current price represents its lowest level since September 23, 2009 on the back of falls in the order of 40 per cent this year.

The commodity has barely paused for breath during a remarkable retreat over the past two-and-a-half weeks, with just one positive trading session in the last 16 as investors fret about surging supply from majors BHP Billiton, Rio Tinto and Vale at a time when Chinese demand is showing signs of fatigue.

The fall has already claimed two juniors in the iron ore space in Australia and is seen impacting a host of others, including US-based Cliffs Natural Resources, which has chosen an unfortunate time to offload its Australian iron ore assets.

"The big three [BHP, Rio and Vale] are in control, and there's not much you can do about it," Lourenco Goncalves, chief executive of Cliffs said earlier this week.

Analysts have largely been revising their forecasts lower in recent months, though Westpac’s chief economist Bill Evans yesterday bucked the trend by issuing a forecast for prices to rebound above $US100 a tonne next year.

Mr Evans also tipped a “probable jump above $US120 a tonne in 2016, according toThe Australian.

A more downbeat assessment has been offered by Alberto Calderon, however, with the former senior BHP executive suggesting the price has further to fall.

“On one side, we will see almost no growth in Chinese demand for iron ore, even if there is some growth in steel,’’ Mr ¬Calderon said.

“On the other side, we are seeing a wall of iron ore supply being dropped in to the market by the large mining companies. It is not difficult to see why iron ore prices have collapsed and why they will go even lower.’’

Mr Calderon suggested prices in the $US70s could be seen for the next couple of years.

Should that forecast come true it would represent a major risk to 13 mines in Australia, according to recent analysis from CLSA analyst Ian Roper.