Riverside Resources reported assay results from seven holes totaling 530.1 metres in its Phase 2A summer 2026 core-drilling campaign at the Union Project in northwest Sonora, Mexico. The program expanded exploration of carbonate-hosted replacement deposits (CRDs), mineral bodies formed when hydrothermal fluids replace carbonate rock, while testing new targets and district-scale extensions. At Union Norte, hole UND26-015 intersected 14.60 metres grading 0.45 g/t gold equivalent from 1.0 metre, including 4.60 metres at 1.09 g/t gold equivalent, while UND26-014 returned 9.10 metres at 0.76 g/t gold equivalent from 1.90 metres, including 1.50 metres at 3.38 g/t. Riverside said the results support continued drilling of a near-surface, northwest-trending feeder structure. Hole UND26-013 at Union Mine intersected lead-zinc mineralization south of historic Sproul manto workings, indicating proximity to a replacement body. An induced-polarization survey at Luis Hill outlined a chargeability anomaly extending more than 1 kilometre along strike and about 200 metres in depth in one description, and 300 metres at depth in another, coinciding with a sediment-hosted gold target identified during Phase 1 drilling. Riverside plans to resume Phase 2B drilling after the monsoon season, which typically ends toward late September or early October 2026, at Union, Union Norte, Luis Hill and Jabali. The company is evaluating reverse-circulation drilling to improve penetration in faulted ground while retaining diamond drilling where detailed geological information is needed. Questcorp Mining is earning into the project under an option agreement dated May 6, 2025. Riverside CEO John-Mark Staude said grades above 0.5 g/t are significant because mines in the region produce at that grade or higher, while describing the near-surface results and mineralization at Union and Union Norte as encouraging. The release states that the reported gold-equivalent calculations are illustrative and use specified metal prices, recoveries and payability factors. It also says no quality-control or quality-assurance failures were identified in the reported batches.