Announcement • Jul 08
Radisson Mining Resources Reports Highest-Ever Assay Result At O'brien Gold Project
Radisson Mining Resources Inc. announced the results of three new drill holes recently completed at its 100%-owned O'Brien Gold Project located in the Abitibi region of Québec. The three holes are from separate areas of exploration focus within the ongoing 140,000 metre step-out drill program. The results include the highest drill assay ever achieved in the Project's history: 1,603.95 grams per tonne gold over 1 metre within a mineralized interval of 316.31 grams per tonne gold over 5.1 metres (core lengths). This record-setting intercept is in hole OB-26-385W4, which was targeting the deep extension of vein mineralization hosted within Piché Group rocks beneath the former mine workings (O'Brien Mine East). The intercept, characterized by extensive visible gold, was observed in Pontiac Formation rocks at 823 metres downhole, before the target area was reached. It represents, potentially, a new zone of very high-grade mineralization, outside the scope of the main mineral resources and previously unrecognized. Highlights of the three holes released include: O'Brien Mine East: OB-26-385W4 intersected 316.31 grams per tonne gold over 5.1 metres (core length) including 1,603.95 grams per tonne gold over 1.0 metre and 3.97 grams per tonne gold over 5.0 metres including 10.47 grams per tonne gold over 1.3 metres. Trend #1: OB-26-384W1 intersected 46.22 grams per tonne gold over 3.9 metres including 132.28 grams per tonne gold over 1.3 metres and 2.72 grams per tonne gold over 17.5 metres including 10.81 grams per tonne gold over 2.0 metres and 2.39 grams per tonne gold over 29.0 metres including 6.08 grams per tonne gold over 2.5 metres. Trend #1-Trend #2 Gap: OB-26-386W3 intersected 8.60 grams per tonne gold over 2.6 metres including 13.87 grams per tonne gold over 1.5 metres and 2.74 grams per tonne gold over 11.4 metres including 14.64 grams per tonne gold over 1.1 metres. The former O'Brien Gold Mine had a reputation for extremely high-grade gold mineralization. In December 2024 a drill intercept of 1,345 grams per tonne gold over 1.0 metre (within 643 grams per tonne gold over 2.0 metres) was released, interpreted as the extension of the famous O'Brien "Jewellery Box" mining stope. Now, this result has been exceeded with 1,604 grams per tonne gold over 1.0 metre (within 316 grams per tonne gold over 5.1 metres) from a new mineralized zone hosted within Pontiac meta-sedimentary rocks, the formation that forms the hanging wall of the Piché rocks that host both the bulk of the Project's gold mineralization and the former mine workings. It occurs within a cluster of previously published gold intercepts, offering the potential for a new, very high-grade zone of mineralization outside of the scope of the Project's current mineral resources. Drill hole OB-26-384W1 has returned multiple intercepts of high-grade mineralization in classic quartz vein/alteration packages at the Project's Trend #1, filling in the deep extension of this important target area between 1,600 and 1,700 metres depth. The results reinforce three key exploration themes at O'Brien: the potential for new high-grade mineralization in Pontiac rocks; continued extension of O'Brien gold mineralization and mineral resources at depth, and; additional mineralization within previously under-drilled gaps. Gold mineralizing quartz-sulphide veins at O'Brien occur within a thin band of interlayered mafic volcanic rocks, conglomerates, and porphyritic andesitic sills of the Piché Group occurring in contact with the east-west oriented Larder Lake-Cadillac Break. Gold, along with pyrite and arsenopyrite, is typically associated with shearing and a pervasive biotite alteration, and developed within multiple Piché Group lithologies and, occasionally, the hanging-wall Pontiac and footwall Cadillac meta-sedimentary rocks. As mapped at the historic O'Brien mine, and now replicated in the modern drilling, individual veins are generally narrow, ranging from several centimetres up to several metres in thickness and are associated with broader, mineralized alteration envelopes. Multiple veins occur sub-parallel to each other, as well as sub-parallel to the Piché lithologies and the Larder Lake-Cadillac Break. Individual veins have well-established lateral continuity, with steeply plunging grade shoots developed over significant lengths. The historic O'Brien mine produced over half a million ounces of gold from such veins and shoots at an average grade exceeding 15 grams per tonne gold and over a vertical extent of at least 1,000 metres. Modern exploration has focussed on delineating well-developed vein mineralization below and to the east of the historic mine. Based on the historic data available, it is clear that the former mine was "high-graded", with mining focussed on a main central stope and parallel veins identified but left undeveloped. Since the end of 2024, Radisson has been pursuing a program of broad step-outs beneath the historic O'Brien Gold mine and the existing mineral resources designed to test the extent of gold mineralization at the Project. This drilling is accomplished with pilot holes followed by wedges and directional drilling to maximize drill efficiency and minimize costs. In October 2025, Radisson announced the expansion of the step-out drill program to 140,000 metres employing eight drill rigs. The origin of the step-out drill program was the deep pilot hole OB-24-337, which was the first exploration drill hole located below the former mine workings since mining ended in 1957. This hole intersected 31.24 grams per tonne gold over 8.0 metres, including 242.0 grams per tonne gold over 1.0 metre at approximately 1,500 metres vertical depth. Fifteen wedge branches were completed from OB-24-337 delineating up to eight gold-bearing veins over a 250-metre by 700-metre area in what is referred to as "O'Brien Mine East". In March 2026, Radisson published an interim update in the Project's mineral resources, showing meaningful growth based on the on-going drilling. The focus of the step-out drill program has been the extension of mineralization at depth, with an exploration floor of 2 kilometres depth, and recently announced plans to extend this drilling to 2.5 kilometres depth. Given the character of neighbouring gold deposits and the wealth of mining infrastructure within or close to the O'Brien Gold Project, Radisson believes that significant exploration potential exists to these depths, and such mineralization might reasonably be expected to be developed. In the results, drill hole OB-26-385W4 was the fourth wedge from the pilot hole targeting the O'Brien Mine East area between the base of the former mine and the OB-24-337 wedge cluster.
