Mosaic Conducts a Helicopter-Borne Magnetic Survey and Obtains Impact Work Permits on Golden Island

Mosaic Minerals Corporation has completed a helicopter-borne magnetic survey across its entire Golden Island property in Quebec and secured impact work permits from the Quebec Ministry of Natural Resources, positioning the company for a planned spring 2026 drilling campaign. The new high-resolution magnetic data will be integrated with extensive historical datasets to guide exploration planning on this historically significant gold property located on Tiblemont Island near Senneterre.

The Golden Island project carries substantial historical significance, having been discovered in 1932 by Dr. Theodore Koulomzine and developed by Tiblemont Consolidated until World War II halted operations in 1939. During this period, extensive infrastructure was established including 3,350 linear meters of trenches, a 155-meter three-compartment shaft, a 360-meter adit, and 1,800 meters of underground development. A historical resource estimate, though not NI 43-101 compliant, indicates 391,000 tons at approximately 2.8 g/t gold at shallow depths under 60 meters, suggesting potential for open-pit mining methods.

Subsequent exploration work, particularly SOQUEM's 1982 drilling program, validated the mineralization with notable intersections including 17.7 meters at 1.18 g/t gold (including 5.6 meters at 2.99 g/t) and 14.4 meters at 1.25 g/t gold in the main zone. Additional mineralization was identified approximately 1 kilometer northwest of the main zone, where drilling intersected 4.7 meters grading 1.31 g/t gold, associated with the same magnetic anomaly as the main shaft area.

The completion of permitting milestones and acquisition of new geophysical data represents a significant advancement for Mosaic's exploration strategy in the prolific Abitibi gold camp. The integration of modern magnetic survey data with the property's extensive historical database should provide enhanced targeting capabilities for the upcoming drilling campaign, potentially unlocking value from this historically productive but underdeveloped gold asset. The year-round accessibility via Regional Road 113 and established infrastructure foundations provide operational advantages for future development activities.