Rumours keep persisting for Rio Tinto, with the miner having a shocker of a session, falling 11.7% or $7.65 to $57.60.

Rio shares also fell 11% overnight in London.

Speculation is mounting that the miner will abandon its much-publicised deal with Chinalco in favour of a rights issue.

"The Chinalco deal was a desperate and short-sighted deal when the credit and equity markets were frozen," Southern Cross Equities director Charlie Aitken told Dow Jones Newswires.

"Today, Rio has a variety of refinancing options and they should use them, even if that means annoying their largest customer."

Rio shares hit a low-point of $57.14 this afternoon, its lowest price this month.

Overall, the All Ordinaries finished the day 3.4% down to 3710.8 points, while the S&P-ASX 200 closed 3.4% down to 3723.4 points.

It was the worst session for Australian shares so far this month.

BHP Billiton didn’t dodge the damage today, losing 6% or $2.13 to $32.30.

Aquarius Platinum closed 15.5% or 92c down to $5.01, while Fortescue Metals Group lost 11% or 32c to $2.62.

In fact, only four companies out of the top 60 resource stocks finished in positive territory today.

Energy Resources of Australia closed 75c (3%) up to $22.65, AngloGold Ashanti added 6c (0.6%) to $9.91, Andean Resources gained 1.5c (1%) to $1.555 and Kingsgate Consolidated closed 2c (0.3%) up to $5.57.

Spot gold was trading at $US924 per ounce at 4:15pm EST.

While gold is back above $900/oz this week, precious metal miners were still hit today with Newcrest Mining falling 2% to $29.53 and Lihir Gold dropping 2.6% to $3.02.

Energy and Minerals Australia rose 17% or 5c to 34c on news of a Supreme Court victory.

NGM Resources also had a positive session after announcing Paladin Energy had increased its stake from 14% to 16.7%.

The explorers’ shares gained 7% or 0.6c to 9.1c.

Base metals were all down overnight on the London Metal Exchange.

Zinc fell 4.6% to $1447.25 per tonne, nickel dropped 4.6% to $12,370/t and copper lost 3% to $4428/t.