Announcement • Jan 23
Riverside Resources Inc. and Questcorp Mining Inc. Channel Sample High Grade Gold-Silver 30M @ 20 G/T Gold and 226 G/T Silver
Riverside Resources Inc. announce, alongside Questcorp Mining Inc. high grade 20.2 g/t Au and 226 g/t Ag with 2.7% Zn in 30 m long continuous chip-channel (‘channel’) sampling from the Union Mine area, plus full complete drill results from the La Union Project in Sonora, Mexico. This news release focuses on the channel sampling and the second and final set of drill results from the Union Mine, Union Norte and El Cobre targets. Highlights of Chip-Channel Sampling and Phase 1 Final Drill Results: Rock chip-channel sampling returned 30m grading 20 g/t Au and 226 g/t Ag along the access wall to the upper part of the Union Mine. Reporting results from the final six holes of the total 12-hole program, with new assays from target areas: Union Mine, Union Norte, and El Cobre that successfully found zinc related to CRD in all 3 areas. The Phase 1 drill program intersected gold in six different drilled targets. Drilling at all three target areas hit Carbonate Replacement Deposit (‘CRD’) style of mineralization with favorable indications, including anomalous levels of zinc, silver, gold, and lead, consistent with previous mining and positive for the program. Drilling at Union Mine found upper parts of possible Carlin-like sediment-hosted gold indicators, with the favorable formations in the lower carbonates above the productive shales which can be immediate focus for Phase 2 exploration program. Questcorp announced on January 13, 2026: drilling at Luis Hill intersected a sediment-hosted gold target with 42 m at 0.3 g/t gold in black shales and carbonate strata similar to Carlin Nevada style. This first hole is now to be followed up and provides expansive gold potential. Chip-channel Sampling, Union Mine Area: Rock wall chip-channel sampling at the Union Mine returned high grade gold and supports follow-up exploration, with the potential to drill from the upper most mine workings or from surface to expand upon the 30m grading 20 g/t gold zone. Full assay results for the gossan oxide samples are provided in table 1 below and include high-grade zinc, which is typical of CRD systems in the region. Comparable zinc- rich CRD mineralization occurs at the Hermosa Project with the Taylor Deposit, which USD 10 billion value major mining company South32 is currently advancing in southernmost Arizona near the Sonora border, immediately northeast of the Union Project where South32 is investing USD 2.1 Billion in Capex (South32 corporate disclosure, 2025). Riverside's project is separate from South32's and is included as a comparison to illustrate the target deposit type and the potential scale of similar deposits. Arizona and Sonora have both been major mining jurisdictions for these deposit types for more than 150 years. To date, the Union Project has not been investigated as extensively as South32's Hermosa Project. On the cross section, holes 1 and 8 are shown along with the gold-rich channel sampling results. The cross section provides context for the 30 m gold-silver-zinc sampling interval relative to several known ore bodies and highlights areas where follow-up and expansion work could be completed at the Union Mine area, particularly to the right (southeast). Drilling completed across the district has helped define the stratigraphy and identify SHGD-style mineralization that is comparable to eastern Nevada. Within the Union Mine area, historic mine workings related to the CRD system were intersected in drill hole 8, with additional indications of CRD-related metals at the bottom of the hole. The hole also encountered manto horizons along its length, including 15.85m averaging 214 ppm Zn in dolomitized limestone. Drill hole 7 also intersected zinc mineralization in the Union Mine area, returning 14m averaging 0.1% Zn, although this hole is located to the north. The drill map highlights the Union Mine area as well as Union Norte, Luis Hill and El Cobre. This news release provides the data for the three target areas and includes commentary about the significance of Luis Hill. The drilling and sampling at the Union Mine area is located in the red oval labelled Union Mine, and the cross section with the upper area of the past ore bodies at Union Mine and the new sampling with high grade zinc, silver and gold in the oxide zone accessed at from the surface mine decline. Union Mine, with CRD in past oxide operations, had three holes drilled in this round (UND25-1, 7, 8). Drilling intersected zinc in the right types of alteration for the CRD, and drilling was lost when it hit underground workings. Follow-up drilling will be completed to better test these precious and base metal zones, and particularly the SHGD potential. Hole 9 was drilled vertically in the southern part of the Luis Hill target, a large 1,500m by 500m magnetic high. Although the hole did not intersect an obvious large magnetic source, it cut several magnetic dioritic dikes, which may be related to a deeper and larger magnetic body, likely an intermediate- composition intrusion. The discovery interval comprises gold hosted in silica replaced black shale, jasperoid-like dolomite and silica-flooded siltstone, which is comparable to some sediment-hosted gold deposits in Nevada (Carlin Deposits, USGS Prof. Paper 1267, 1985). This represents a new finding for this part of Sonora and is significant for both the property and the region, as it indicates potential for previously unrecognized sediment-hosted gold within one of Mexico's most prolific gold belts, the Sonora Gold Belt (also referred to as the Megashear Gold Belt in past scientific studies). Folding and Basin and Range block faulting are expected to bring the mineralized formations closer to surface, supporting additional drilling in first half 2026 within the magnetic target area. Riverside and Questcorp believe Luis Hill has the potential to become a major new discovery in Mexico. A new discovery at Luis Hill has identified previously unrecognized Carlin-like, sediment-hosted gold mineralization in black shales and carbonate strata, returning 0.3 g/t gold over 42m, with results to date indicating sulfides, mineralization styles, and intrusions consistent with a carbonate-hosted metal system. The 42m interval comprises 23 assay intervals ranging from 0.45m to 2m in width, with gold values from 0.005 g/t to 1.31 g/t; fifteen intervals returned greater than 0.1 g/t Au, including three intervals exceeding 0.5 g/t Au. This style of thick, continuous mineralization is new for this part of Sonora.
