An updated definitive feasibility study (DFS) on ASX-listed Hastings Technology Metals' Yangibana rare earths and niobium project, in Western Australia, has provided a derisked pathway to Stage 1 production.

The project economics for Stage 1 of the project include a pre-tax net present value of $649-million and an internal rate of return of 34%, with a 2.4-year payback period.

For an initial capital investment of $333-million, Yangibana Stage 1 can produce 37 000 t/y of concentrate over a 19-year mine life.

The project is held through the Yangibana joint venture (JV), in which Wyloo Gascoyne has a 60% stake and Hastings 40%.

The updated DFS reflects current capital and operating cost estimates, updated market-based rare earths pricing forecasts, an owner-operator mining model and the site infrastructure already built on site.

Stage 1 comprises a simple openpit mining operation and beneficiation plant using conventional flotation processes with a targeted 85% total rare earths oxide (TREO) recovery rate.

The DFS finds the Stage 1 project can generate average earnings of A$108-million a year, after royalties, which total earnings of A$2.03-billion possible over its lifetime.

The DFS also confirms a low-cost operating profile, with a life-of-mine average cash operating cost estimated at A$162/t on a run-of-mine basis, or $20.75/kg of TREO in concentrate.

Notably, the DFS is based on a total ore reserve of 20.93-million tonnes grading 0.90% TREO, with no production attributed to inferred mineral resources.

Stage 1 has deliberately been sequenced as a capital-efficient, fast-track route to production from one of the world's highest-grade neodymium and praseodymium (NdPr) rare earth ore bodies.

Hastings confirms that NdPr represents 37% of the contained TREO in the ore reserve and will generate more than 90% of the project's expected revenue.

At a concentrate grade of 27% TREO, Yangibana is poised to produce 8 524 t/y of TREO in concentrate, particularly 3 090 t/y of NdPr concentrate.

The company says more than $160-million worth of infrastructure and long-lead items have already been delivered to site in respect of Stage 1 of Yangibana's development. The already constructed items include a 294-room accommodation village, an airstrip, a main access road, communication towers and water borefields.

Equipment for the beneficiation plant has been procured, which reduces capital risk and time to first production.

Hastings affirms that environment and statutory approvals required to construct and operate Stage 1 have already been secured.

Hastings CEO Vince Catania comments that the updated DFS confirms what the JV partners have long believed about Yangibana, that it is one of the highest-grade NdPr deposits in the world and that positive economics underpin the Stage 1 development plans.

With the updated DFS now complete, Wyloo has started with a process to sell its 60% interest in the venture, with the company having received strong interest from a range of domestic and international parties.