Mining company Xstrata has opted out of a joint venture to develop Altona Mining Limited's large copper project in north-west Queensland.
After reviewing an independent valuation, Xstrata has decided not to buy 51 per cent of the Roseby Project, north of Cloncurry.
Altona's managing director Alastair Cowden says the project will still go ahead if a suitable partner can be found.
"In common with many other companies the challenge is how does one fund it and make it into a reality?" Mr Cowden said.
"I think if it can become a reality it will be there for decades.
"Our challenge is to find the right partner or strategic deal to make it happen." Mr Cowden says the decision will allow Altona some flexibility as it moves to progress the project.
"I guess like every decision there are positives and negatives," he said.
"Xstrata are a very experienced mining company and have been operating in the Isa area for a long, long time so clearly we would have benefited from that.
"However, there was a particularly set structure [to] the deal and now we have a lot more flexibility to probably generate more value for shareholders."