THERE was no apparent reason for OZ Minerals shares to rise by more than 5 per cent on Friday, but there was a damn good reason for them to be up by almost 3 per cent on Monday.
The Melbourne-based miner revealed encouraging news about its copper and gold operations in South Australia on Monday, which now appear to be more prospective than first thought.
The Carrapateena deposit - which ranks as OZ's main growth project - now boasts an "indicated" 202 million tonnes of ore with at least 0.7 per cent copper.
The term "indicated" is an official standard under the code by which ASX-listed companies must report the prospectivity of their mineral deposits.
"Indicated" resources are more certain than those categorised as "inferred", and OZ said if both categories were combined, the amount of known copper and gold at Carrapateena is now 43 per cent higher than when it bought the asset just under two years ago.
There was further good news to be found just 10 kilometres north-west of Carrapateena, where OZ has found another deposit named "Khamsin" that is prospective for copper and gold and will be drilled extensively this year.
The growth assets are crucial to OZ given that its flagship asset, Prominent Hill, appears to be declining in grades and output. A drilling campaign is under way to try and extend the life of the mine.
OZ Minerals shares closed 20¢ higher at $7.50. When added to Friday's unexplained rise of 36¢, the stock has risen more than 7 per cent in the past two trading days.