Estrella Resources Advances Major Limestone Project in Timor-Leste
Estrella Resources has successfully cleared another significant milestone at its Werumata limestone project in Timor-Leste, with the complete receipt of assay data from its inaugural drilling campaign conducted last year. This development solidifies the company's position in the region's burgeoning mining sector.
Drilling Campaign Reveals Extensive Limestone Deposits
The 2025 exploration program involved 33 reverse-circulation (RC) and nine diamond drill holes, totaling 42 holes and 3,717 metres across two expansive limestone plateaus near the coastal town of Uero-Mata, a strategic location with potential port infrastructure. The final assay results strongly corroborate earlier preliminary data released in February, which highlighted broad, low-impurity limestone intercepts and identified a potential inferred resource target of 500 million tonnes.
Drilling operations intercepted substantial thicknesses of Baucau limestone, reaching up to 87 metres with an average of 30 metres, while underlying Batu Putih Chalk intersections extended up to 59 metres, also averaging 30 metres in depth. Estrella reports that the younger Baucau limestone averaged 33.15 per cent calcium, equivalent to 83 per cent calcium carbonate, and the Batu Putih Chalk averaged 31 per cent calcium or 77.5 per cent calcium carbonate.
Low Impurity Levels Enhance Industrial Suitability
Notably, the Baucau limestone exhibited low magnesium levels, averaging only 2.05 per cent magnesium oxide, along with minimal alumina content at 1.83 per cent and iron oxide at 0.96 per cent. This composition indicates a clean lime product that is particularly well-suited for industrial acid-neutralisation applications, such as in nickel processing and other chemical industries.
"Estrella continues to develop highly exciting prospects in the virtually unexplored region of Timor-Leste, and we are very pleased to report the remaining assay results from the Werumata limestone project," said Estrella Resources managing director Chris Daws. "The results confirm the presence of a large amount of limestone and chalk, evident from broad intersections of clean lime with low impurities."
Strategic Partnerships and Future Plans
The drilling program also provided valuable insights into local stratigraphy, identifying a variable marl unit beneath the limestone and chalk sequences. Marl, a natural soil conditioner composed of clay and calcium carbonate, has historical uses in agriculture for neutralising acidic soils and improving crop yields. This geological data will support Estrella's upcoming modelling efforts.
Looking ahead, the company is focusing on determining the bulk density of the materials, collaborating with the Universidade Nacional Timor Lorosa’e (UNTL) to complete necessary measurements. Full density results are expected by the end of March, paving the way for a maiden mineral resource estimate scheduled for mid-April.
In a strategic move last May, Estrella entered into a binding master agreement with Indonesian mining and energy services firm PT Raka Energi Mandiri (REM), granting exclusive marketing and off-take rights for its high-grade calcite-rich limestone. To incentivise performance, REM will receive up to 500 million performance-based share options exercisable at five cents per share if Estrella achieves the shipment of 500 million tonnes within five years of initial production.
To execute this strategy, the parties have established a joint venture company, Estrella Murak Rai Timor Lda., with Estrella holding a 70 per cent stake and Timor-Leste's state-owned Murak Rai Timor owning the remaining 30 per cent. This joint venture will capture all revenue from limestone sales, targeting Indonesia's booming demand for limestone, especially in nickel processing and other industrial sectors.
If successful, the Werumata project could emerge as a significant bulk limestone operation, leveraging its coastal location for efficient port access—a combination likely to attract substantial market interest.
