Sentinel Exploration Limited is pleased to announce that it has successfully completed its second drilling campaign at the Company’s 100% owned Marda East Gold Project, located near Southern Cross in Western Australia.
HEADLINES
- Second RC drilling campaign successfully completed at Sentinel’s 100%-owned Marda East Gold Project near Southern Cross, Western Australia.
- 33 RC holes completed for a total of 2,915 m, targeting infill drilling and extensions to areas where the maiden program intersected gold mineralisation.
- Samples have been submitted for assay, with results to be released once received, validated and interpreted by the Company.
- Program follows the maiden 2,200m RC campaign completed in Q4 2025, which intersected gold mineralisation in 16 of 29 RC holes.
- Previously reported maiden drill results include 3 m @ 8.61 g/t Au from surface, 3 m @4.75 g/t Au from 48 m and 6 m @ 1.64 g/t Au from 12 m, supporting the completed follow-up drilling program to better define continuity, geometry and potential scale of mineralisation1.
Sentinel’s Managing Director Simon Adams, commented:
“Completing a further 2,915 m of drilling across 33 RC holes is an important step at Marda East. The program commenced shortly after Sentinel’s NSX listing in April and was designed to follow up the maiden drilling results, including shallow high-grade gold from surface, and to test priority areas for continuity and scale. With over 5,000m of drilling now completed at Marda East, we are continuing to build our understanding of the geology and mineralisation potential of the project. We look forward to updating shareholders once assay results have been received and interpreted.”
The completed program comprised 33 reverse cycle (RC) drill holes for a total of 2,915 m. The campaign was designed as a follow-up to the Company’s maiden RC drilling program carried out in November 2025, with drilling directed at infill targets and extensional to areas where shallow gold mineralisation was identified in the maiden program.
Samples from the program have been submitted for laboratory assay. Sentinel will report results to the market once assays have been received, checked and interpreted. No new assay results are being reported in this announcement.
The follow-up program provides Sentinel with a larger dataset to assess whether mineralisation demonstrates continuity within the previously identified anomalous gold system, and to refine the Company’s understanding of the geometry and priority areas for future exploration.
10 samples have been submitted for petrographic analysis to accurately define rock types and mineralised zones.
Figure 2: Drill rigs at Marda East Project
Next Steps
• Receive and validate laboratory assay results from the completed 33-hole RC drilling program.
• Integrate the new assay data with the maiden drilling results, soil geochemistry and geological interpretation for Marda East.
• Use the results to refine targets for follow-up drilling and assess whether further work is warranted to better define continuity and scale of mineralisation.
• Review results from samples submitted for petrographic analysis to accurately define rock types and mineralised zones.
Figure 1: Marda East WA location map
Competent Person Statement
The information in this announcement that relates to exploration results and geological interpretation is based on information compiled by Mr Adam Anderson, a Competent Person who is a Member of the Australasian Institute of Mining and Metallurgy. Mr Anderson has sufficient experience relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr Anderson is a consultant to, and substantial shareholder of, the Company. Mr Anderson consents to the inclusion in this announcement of the matters based on his information in the form and context in which it appears.
Forward Looking Statements
This announcement may contain forward-looking statements, including statements relating to planned exploration activities and future work programs. Forward-looking statements are subject to risks and uncertainties and actual results may differ materially from those expressed or implied. The Company does not undertake to update forward-looking statements except as required by law.
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Company News Release
Date: 28 May 2026
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Sentinel Exploration Limited’s is a newly listed Western Australian mineral exploration company with a focus on Gold, Copper and Lithium opportunities.
Listed on the National Stock Exchange of Australia under NSX: SOX, Sentinel is focused on advancing mineral discovery opportunities across its WA project portfolio.
The company’s flagship Marda East Gold Project delivered encouraging shallow gold results incl. 3m @ 8.6g/t gold with follow-up drilling a priority.
