UPDATE 2.45pm: Shares in BC Iron fell after the iron ore miner warned of a reduced rate of production at its Nullagine joint venture project as it deals with ore quality issues.
The company said it had encountered ore with higher clay content while expanding its footprint to new ore sources.
It said it had begun several initiatives to better anticipate and manage product quality and ore handling.
BC had agreed with joint venture partner Fortescue Metals Group (25 per cent) that the rate of production and haulage would be reduced while the initiatives were underway.
The company said September quarter sales from Nullagine would be three ships (500,000 wet metric tonnes) below expectations.
However the company expected to be able to catch-up at least two of these shipments during the following three quarters.
BC therefore maintained its previous full-year sales guidance of 5.8-6.2 million wet metric tonnes of ore.
"The company is currently considering any impact of the new initiatives outlined above on its C1 cash costs guidance of $49-53 per wet metric tonne for full-year 2015 and will advise the market if there is a material change," BC said in a statement.
The company would update the market as more information became available.
BC shares closed down 15 cents, or 4.76 per cent, at $3.