PERTH (miningweekly.com) – An updated scoping study into the Yangibana rare earths project, in Western Australia, has resulted in a higher capital cost estimate, as well as a shorter mine life.

A 2014 scoping study estimated the project would require a capital investment of A$390-million to deliver around 2 700 t/y of neodymium oxide, 750 t/y of praseodymium, 40 t/y of dysprosium oxide and 70 t/y of europium oxide over a 15-year mine life.

The project was, at that point, estimated to have a net present value (NPV) of between A$900-million and A$1.2-billion.

Hastings Technology Metals on Tuesday said the updated scoping study focused on the production of separated oxides of the rare earths neodymium, praseodymium, dysprosium and europium, with lesser gadolinium and samarium. Additional rare earths could be considered for processing at a later date if suitable market opportunities were identified.

Maintaining the mining rate of one-million tonnes a year, the updated scoping study estimated the project would require a capital investment of A$411-million.

It was estimated that some 45 000 t/y of concentrate would be produced from the Bald Hill South and Fraser’s deposits, while the Yangibana deposit would deliver an additional 70 000 t/y of concentrate, over a seven-year mine life.

Only indicated resources would be mined during the current seven-year mine plan and would deliver a NPV of between A$650-million and A$750-million.

Hastings noted that, based on the mining and processing of some 15-million tonnes of comparable materials, the Yangibana project could return a NPV of between A$900-million and A$1.1-billion. This expanded mining scenario was based on the current inferred resource of 4.2-million tonnes and an exploration target of between four-million and seven-million tonnes.

With the updated scoping study now in place, Hastings was progressing prefeasibility study work on the Yangibana project, with that study due for completion in the first quarter of 2016.