A rare earth mine in the remote Kimberley region of Western Australia is a step closer to reality, after the release of Northern Minerals' final feasibility study.

The company said the feasibility study had confirmed its Browns Range project, 160 kilometres south-east of Halls Creek, was viable and profitable.

It already has state environmental approval and Northern Minerals recently secured a $49.5 million funding partnership with Jien Mining.

Production has been postponed to the second half of next year but the life of the mine has been extended 16 per cent to 11 years.

The company said it was now on track to be the world's first dysprosium supplier outside of China.