The materials index slumped 2%, on lower metal prices, after US Federal Reserve chairman Ben Bernanke hinted that there would be no further quantitative easing to stimulate the economy.

The S&P/ASX 200 lost 1% or 43.05 points to 4255.5 points, posting the heaviest loss of key indices in the region, after hitting an intraday low of 4248 points during morning trade.

Rio Tinto dropped 1.8% or $A1.20 to $66.25 while BHP Billiton fell 1.5% or 55c to $35.55.

Newcrest Mining dropped 2.8% or 94c to $32.55 after gold took a hit in the wake of Bernanke’s comments.

New Hope Corporation fell 4.9% or 28c to $5.43 after it said its sale process failed to garner adequate bids.

A standout amongst the top stocks was magnetite pellet producer Grange Resources, which gained 5.5% or 3.5c to 67c after posting a $216.6 million profit yesterday.

Macquarie Private Wealth retained an outperform rating for Grange but has upped its 12-month target price by 5c to $1.

Smaller magnetite hopeful Mindax jumped nearly 19% or 3c to 19c after announcing a deal with Japan’s Sumitomo Corporation for the Mt Forrest project that could be worth as much as $115 million.

New market darling Blackthorn Resources continued a stellar run today after announcing further wide, high-grade copper hits from its Mumbwa project in Zambia.

An announcement last Thursday sent Blackthorn shares up 44% from 74.5c to $1.025 and the stock has posted further gains in four out of the last five sessions.

Blackthorn shares jumped a further 25% or 37c today to $1.82.

Western Areas and Kagara went into trading halts pending news of a corporate transaction.