Bukit Besi Iron Project 2026 Mineral Resource Estimate Update: Key Insights for Investors

Executive Summary

Fortress Mining Sdn. Bhd. has released a comprehensive Summary Qualified Person’s Report (SQPR) for the Bukit Besi Iron Project, detailing a significant update to its Mineral Resource Estimate (MRE) as at 28 February 2026. This report, compiled independently by Michael Andrew of Datamine Australia Pty Ltd (Snowden Optiro), was prepared for compliance with the Singapore Exchange’s Catalist Rules and the 2012 JORC Code.

Key Points for Investors

• Substantial Resource Growth: The updated MRE indicates a 25% increase in total resources year-on-year, now standing at 14.49 million tonnes (Mt) grading 40.62% Fe. This is a material increase of 2.94 Mt from the previous estimate, primarily attributed to extensive additional drilling conducted in 2025 and improved geological understanding.
• Resource Classification: The majority (91%) of the resource is classified as Inferred, with 9% classified as Indicated. Indicated resources are mainly in near-surface, closely drilled areas. This classification reflects ongoing efforts to improve data quality and geological understanding.
• Operational Performance and Reconciliation: High-level reconciliation between the model and actual production data demonstrates strong alignment, with 2.22Mt @ 32.31% Fe identified in the MRE for 2025 against approximately 2.75Mt mined and 2.1Mt processed, highlighting the reliability of estimates.
• Production Metrics: Bukit Besi produced approximately 683,000 tonnes of iron concentrates between March 2025 and February 2026, underscoring the project’s ongoing operational performance and revenue generation potential.
• Geological and Mining Context: The Bukit Besi deposit is a skarn-type iron ore body with magnetite and hematite mineralisation, hosted along the contact between Palaeozoic sediments and late Cretaceous granite. The mineralisation occurs in three main domains: West, Valley, and East, with strike lengths of up to 400m and vertical extents up to 150m.
• Drilling and Data Integrity: As of 2026, a total of 614 holes (56,809.9m) have been drilled at the project. Improvements in RC sample recovery, QAQC protocols, and laboratory procedures have been implemented, with ongoing database modernization efforts. However, RC sample recovery remains a risk factor (averaging 65%) which is being mitigated by visual discrimination practices in open pit mining.
• Cut-off Grades and Reporting: The MRE is reported at a cut-off of >20% Fe and magnetic susceptibility >30, with recommendations to continue calibrating the cut-off grades against production data to enhance reliability.
• Resource Estimate by Area (as at 28 February 2026):
  • East: 1.46Mt @ 32.57% (Inferred) and 0.16Mt @ 35.05% (Indicated)
  • Valley: 10.94Mt @ 42.00% (Inferred) and 0.74Mt @ 44.04% (Indicated)
  • West: 1.01Mt @ 35.04% (Inferred) and 0.34Mt @ 38.78% (Indicated)
• Permitting and Tenure: The project is secured under two granted mining leases (ML4/2013 and ML7/2013), valid until 2033. There are no known material legal, environmental, or native title impediments.
• Metallurgical and Environmental: The operation produces multiple iron concentrate products using a versatile processing plant. No significant deleterious elements have been reported in product shipments, and all necessary environmental permits and licenses are in place.

Potential Price-Sensitive Issues

• Significant Resource Upside: The 25% increase in total resources is a strong positive, potentially supporting a longer mine life and higher future production, which could positively impact share valuation.
• Predominance of Inferred Resources: While the resource base has grown, the high proportion of Inferred resources (91%) means there remains uncertainty regarding the precise tonnage and grade, which may limit immediate conversion to reserves and affect valuation sensitivity.
• Ongoing Drilling and Modernization: Continued infill drilling and data system upgrades are expected to improve resource confidence and potentially upgrade more material to Indicated or Measured categories, providing future upside for investors.
• Operational Risks: Issues such as RC sample recovery and lack of systematic downhole survey for RC drilling remain, though mitigation strategies are in place. Any failure to resolve these could impact future resource classifications.
• Production and Reconciliation Performance: The close alignment between the MRE and actual processed material is a positive sign, but ongoing calibration is needed to maintain this reliability.

Detailed Operational and Technical Information

• Geological Setting: The project is located in the eastern belt of the Malay Peninsula, with mineralisation controlled by NE-SW, NW-SE, and N-S trending structures. Skarn-style magnetite and hematite replacements dominate the ore zones.
• Drilling Techniques: Both RC and diamond drilling are employed. RC sampling uses 1m intervals and riffle splitters, while diamond core is sawed and sampled as half core. Drilling since 2017 has been primarily conducted by internal Fortress contractors.
• Sample Preparation and QAQC: All samples are processed at Fortress’s internal lab with regular submission of pulps to Bureau Veritas for external checks. Quality control includes blanks, certified reference materials, and duplicates, with regular improvements to protocols and procedures.
• Resource Modelling: Ordinary kriging is used for Fe, S, and magnetic susceptibility, with block sizes of 15m x 15m x 3m and sub-celling for accuracy. Hard boundaries are used for domains, and the model is validated statistically and visually, including reconciliation to production.
• Bulk Density Data: Nearly 1,200 water immersion tests and over 400 pycnometer measurements underpin the density model, enhancing reliability.
• Mining and Processing: Conventional open-pit methods are used, with grade control via a 6,000 Gauss magnet. The plant can handle a variety of concentrate streams and has a proven track record of export shipments.
• Exploration Upside: The company continues to pursue infill and step-out drilling, with modern geophysical surveys (magnetic and radiometric) identifying further potential targets.
• Historical Context: The Bukit Besi mine has a long history, with over 36.5Mt @ 63% Fe mined up to 1965. Modern exploration and mining were revived in 2012, positioning Fortress as the current operator since 2016.

Conclusion

The 2026 Bukit Besi Iron Project Mineral Resource Estimate marks a substantial improvement in resource inventory and model reliability, driven by ongoing drilling, operational enhancements, and robust QAQC. The 25% resource increase and strong reconciliation with production data are key positives. However, shareholders should remain aware of the high proportion of Inferred resources and ongoing operational risks related to RC sampling. Continued drilling, data improvements, and resource upgrades are expected to deliver further upside and could materially impact future share performance.

Disclaimer: This article is a summary and interpretation of the official Summary Qualified Person’s Report for the Bukit Besi Iron Project as at 28 February 2026. It is provided for informational purposes only and should not be considered investment advice. Investors are encouraged to consult the full report and seek independent financial advice before making investment decisions.

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