Tier One Silver intercepts 448.2 g/t Ag, 0.37 g/t Au over 1 m at Curibaya

Vancouver, British Columbia--(Newsfile Corp. - June 11, 2026) - Tier One Silver Inc. (TSXV: TSLV) (OTCQB: TSLVF) (FSE: TOV0) ("Tier One" or the "Company") is pleased to announce the second and final round of assay results from its Phase 2, eight diamond core drill program at its high-grade Curibaya epithermal silver-gold-copper project located in Tacna, Peru. All four of the final holes drilled in the Cambaya I corridor intercepted silver and gold with highlights including 1.0 metre ("m") of 448.2 grams per tonne ("g/t") silver ("Ag") and 0.37 g/t gold ("Au"), within a broader interval of 4.0 m of 136.2 g/t Ag and 0.15 g/t Au, in hole 26CUR-023, the seventh hole of the program. These results complement previously released intercepts and further define the scale and continuity of precious metal mineralization within the Cambaya I corridor and across the Curibaya project area drilled to date.

Phase 2 drilling, conducted through the Company's wholly owned Peruvian subsidiary, Magma Minerals S.A.C., totaled 1,133.6 m and represents a focused test of shallow levels along a limited portion of the Cambaya I corridor (Figure 1). Results collectively reinforce the presence of a robust high-grade silver-gold epithermal system which was originally identified in the Company's 2021 surface sampling and inaugural drill campaign. All results from Phase 2 drilling have now been received and are summarized in Table 1 below.

Building on the initial four holes of Phase 2 drilling released April 21, 2026, the remaining results provide additional confidence in the geometry and continuity of mineralized structures, while also identifying new high-grade shoots within the corridor. Located more than 1 kilometre ("km") away from Phase 1 drill hole 21CUR-016, which reported 1.5 m with a grade of 1128.7 g/t Ag and 1.04 g/t Au (see news release dated Fe