Copper miner Antofagasta dampened hopes of a special dividend for 2013 after posting a drop in first-half profit and forecasting challenging market conditions.

Shares in London-listed, Chile-focused Antofagasta have long traded at multiples at the top end of the sector, not least because of its generous shareholder rewards. The company has paid special dividends in nine of the last 10 years.

But less cash coming from its core operations, spending on growth projects and comments on short-term copper weakness dented market expectations, weighing on the stock which fell as much as 5 per cent.

Chief Executive Diego Hernandez anticipated a "return to 35 per cent" payouts as a percentage of earnings, or half the level in 2012 when returns were boosted by a 77½ cent special dividend. – (Reuters)