Rio Grande Resources Confirms High-Grade Gold and Silver Including 46.3 g/t Gold and 1,030 g/t Silver in Channel Samples as it Advances Toward Phase 1 Drilling at its Winston Project, New Mexico

Highlights from the May 2026 Surface Sampling Program Include:

Up to 46.3 g/t gold and 1,030 g/t silver in channel samples

Up to 67.1 g/t gold in grab samples

Up to 26.1 g/t gold and 348 g/t silver in rock chip samples

VANCOUVER, BC / ACCESS Newswire / July 6, 2026 / Rio Grande Resources Ltd. (CSE:RGR)(OTCQB:RGRLF) ("Rio Grande" or "RIO" the "Company"), is pleased to announce results from its recently completed Phase Two surface sampling and structural mapping program (see news release dated May 6, 2026) at its 100%-owned Winston Gold-Silver Project ("Winston" or the "Project") in New Mexico. The program returned multiple high-grade gold and silver results from the Poverty Creek area (see Figure 1), including channel samples grading up to 46.3 g/t gold and 1,030 g/t silver. The field program was completed on behalf of Rio Grande by Dahrouge Geological Consulting USA Ltd. ("Dahrouge") over approximately seven days during May 2026 and included detailed structural mapping together with systematic channel and rock chip sampling over priority target areas on the Project. Collectively, the results further support the interpretation of multiple mineralized structural corridors identified through previous exploration, demonstrating encouraging potential for subsurface continuity and represents compelling targets in anticipation for Rio's Phase 1 drill program.