Estrella Resources (ASX:ESR) has released the results of a Scoping Study for its Werumata Limestone project in Timor-Leste, disclosing a base case after-tax and pre-financing NPV10 of US$1,453 million, an internal rate of return of 46%, and a payback period of 3.5 years, based on a 25 Mtpa operation over a 20-year mine life.

Key Points

  • Base case after-tax and pre-financing NPV10 of US$1,453 million, IRR of 46%, and payback period of 3.5 years
  • Stage 1 start-up capital of US$117 million (including contingency) for an approximately 8 Mtpa operation constructible in approximately six months
  • Total CAPEX of US$476 million for base case development, with a peak funding requirement of US$363 million
  • Low life-of-mine OPEX of US$7.89 per tonne FOB and a base case sales price of US$20 per tonne FOB
  • Development anchored by a signed Master Agreement with PT Raka Energi Mandiri for Indonesian offtake, with scoping-study conditions precedent now satisfied

Staged Development Plan for Werumata Limestone Project

The Scoping Study outlines a three-stage development plan for the Werumata Limestone project via open cut mining, mechanical crushing, and a port facility. Stage 1 involves a start-up operation of approximately 8 Mtpa, constructible in approximately six months. Stage 2, which forms the base case of the study, comprises an expansion to 25 Mtpa through additional berths for large bulk carriers, with construction following Stage 1 through 2029 and ramp-up to full capacity targeted by early 2030. Stage 3 contemplates a future expansion to 50 Mtpa or more, described in the filing as upside and subject to market demand.

Mineral Resource and Financial Parameters

The base case 20-year mine life is underpinned by an Updated JORC (2012) Mineral Resource of 533 million tonnes, comprising 274 Mt Indicated and 259 Mt Inferred, with approximately 51% classified as Indicated. The study applies a sales price of US$20 per tonne FOB, and sensitivity analysis disclosed in the filing indicates that even a Stage 1 development at a reduced price of US$15 per tonne FOB clears Estrella's stated minimum 20% IRR threshold. Capital cost estimates carry an accuracy range of -20% to -50% on the low side and +30% to +100% on the high side, consistent with AACE International Class 5 conceptual estimates.

Regulatory Status and Feasibility Study Pathway

The filing states that the project requires a mining licence, environmental licensing, and maritime and port approvals, none of which have yet been obtained. No debt or equity funding has been secured for the project, and no binding, bankable sales contract has been executed under the Master Agreement with PT Raka Energi Mandiri, which operates as a framework only. The study identifies no fatal flaws. According to the filing, commencement of a Feasibility Study will be subject to Board approval. The company confirmed it is not aware of any new information or data that materially affects the Mineral Resource estimate reported on 15 October 2026.