A company developing a rare earths mine near Alice Springs says the mineral resource is 60 per cent bigger than it previously thought.

Arafura Resources plans to begin mining the Nolans deposit, 130 kilometres north of Alice Springs, in two years.

The company's general manager of project development says recent drilling results show 30.3 million tonnes of rare earths and by-products, compared with their previous projection of 18.6 million tonnes.

Steve Mackowski says it is great news for the Nolans project.

"What that means to us is that whereas we previously reported a life of mine of 20 years plus, we're now looking at either a life of mine of 30 years plus or it gives us the flexibility to increase our production rates," he said.