Rio Tinto trades under investigation after share crash

Some trades in the Australian listing of Rio Tinto are under investigation after the company's stockgranite stone crusher machine in malaysia lost nearly 98 per cent in four minutes and briefly dropped to its lowest level since the 1970s, the Australian Securities Exchange said today.

A series of trades between 11:24 and 11:26 AEST are being investigated, the ASX said. Exchange data shows a series of equity options combinations were traded at $1.43 to $1.91 between 11:24 and 11:26 AEST against a typical price of around $71.00 per share. A total of $489,981 in shares were shown changing hands at the subdued prices, giving an average price of $1.81 per share. However, a trader at Goldman Sachs said the stock had not actually reached that level. "It had something to do with some derivatives and I'm sure it will be unwound later in the day," said the trader, who didn't want to be named. All trades in the stock below $64.35 were cancelled after a review by the market's Dispute Governance Committee, the ASX said later.