- Initial drill program is designed to expand known zones of mineralization, test new targets, and explore areas surrounding multiple historical mine workings within the 25 km² project area.
- Drill program will consist of + 1,500m of diamond core drilling across six holes, each averaging 250m in depth.
- Drilling to test the carbonate-hosted replacement deposit (CRD) style of mineralization, with gold associated with mantos, chimneys, and along structural zones.
- Angled drill holes are aimed at cutting perpendicular to stratigraphic targets and some structural targets which is typical in CRD systems
- Structural features may have served as mineralizing conduits and are key targets in the current drill program.
The recent exploration work over the past three months by Riverside has improved the understanding of the structural geology and stratigraphy in the Sierra El Viejo, the mountain range immediately to the west of La Union Project. The La Union district lies along the flanks of this range, where these updated interpretations help guide current exploration efforts. The exploration target focus is for a large potential gold discovery that expands from previous smaller scale mine operations on the property. The drill program will begin to test the new concepts and expand past previous mining.
Saf Dhillon, President & CEO states, "Questcorp is proud to be working with John-Mark and his whole team at Riverside in what is a historic moment in the development of this property. The La Union Project has had work conducted on it for decades, including the production of 50,000 ounces of gold itself but, it has never had a drill bit pierce the ground until now!"
Earlier this year, Questcorp entered into a definitive option agreement with Riverside's wholly owned subsidiary, RRM Exploracion, S.A.P.I. DE C.V. to acquire a 100% interest in the La Union Project. As part of the agreement, Questcorp issued shares to Riverside, making Riverside a shareholder and aligning both parties' interests in the Project's success. With funding provided by Questcorp, an initial C$1,000,000 exploration program is now underway. This marks the first phase of a larger, C$5,500,000 work commitment, contingent on exploration results and Questcorp's continued participation.
The Drill Program Targets include more than four different areas, beginning with this early-stage stratigraphic and orientation phase of drilling exploration aimed at evaluating the scale of alteration and indications of a mineralized system. This will be the first drilling ever conducted on most of the targets, despite past mining having occurred in the majority of these areas. The initial program will consist of one to three holes per area, primarily for orientation purposes. Follow-up drilling is planned and can be expanded based on initial results, which will help verify the stratigraphy, lithologies, and structural features allowing for improved modeling and next-stage discovery targeting. The four areas are listed below:
- Union Main Mine Area - The program will use angled drill holes to test limestone and other carbonate stratigraphic hosts within the Clemente Formation, with the potential to reach the underlying Caborca Formation. These units are considered the primary hosts for replacement-style mineralization.
- North Union Mine Area - The initial focus of the program will be on testing structural interpretations. Additional drilling is anticipated following this first phase, as results will help guide future drill testing of areas with past mining activity and various structural orientations.
- Cobre Mine Area - The Clemente Formation is the primary host unit, and structural features combined with areas of past mining provide multiple target zones. Drilling will begin with an initial stratigraphic test hole to help orient around the thickness of the host unit and extend into the lower Caborca Formation, which is also a favorable host for CRD-style mineralization.
- Central Union Area - Structural targets, as possible mineralization feeder zones, are a key focus in this past mining manto area. There are extensive additional target zones in the area, and this initial orientation drilling will provide vectoring for the next stage of drilling and further study of the Clemente Formation, and possibly into the Caborca Formation as currently interpreted.
General Overview of La Union Project
The Project is summarized in a recently published NI 43-101 Technical Report available under Questcorp's SEDAR+ profile (www.sedarplus.ca). Riverside initially acquired the Project and subsequently consolidated additional inlier mineral claims, building a strong land position. Riverside then advanced the Project through surface access agreements and drill permitting, making it a turn-key exploration opportunity for Questcorp.
The Project was originally identified through Riverside's exploration work in the western Sonora Gold Belt, conducted in collaboration with AngloGold Ashanti Limited, Centerra Gold Inc., and Hochschild Mining Plc. Earlier research by Riverside Founder John-Mark Staude also contributed to recognizing the district's potential. Initial work by members of the Riverside team, drawing on more than two decades of geological compilation and analysis, further confirmed the region as highly prospective.
At the Project, historical mining by the Penoles Mining Company targeted chimney and manto-style replacement bodies within the upper oxide zones. As a result, the underlying sulfide zones represent immediate and compelling drill targets for further exploration.
The Project features favorable limestone host rocks, an extensive alteration footprint, and multiple small-scale historical workings, with mineralization styles similar to those at the Hermosa Project in southern Arizona. At Hermosa, South32 is advancing mine development following its acquisition of the project from Arizona Mining. On 15 February 2024, South32's board approved a US $2.16 billion capital investment to develop the Taylor zinc-lead-silver deposit, representing the largest private mining investment in Southern Arizona's history. The project is now considered one of the most significant undeveloped base-metal assets in the United States.
At the La Union Project, immediate drill targets offer the potential for significant-scale discoveries. La Union is well positioned for near-term exploration success, with targets that include both oxide and deeper sulfide mineralization.
Figure 1. Geologic map with the tenure of the Union internal concession shown in pink. Manto and chimney type CRD targets are shown as red polygons. All mineral tenures on this map comprise the La Union project. The drill program will focus on the Union Mine and areas north of the Union Mine with the initial drill work.
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10197/261433_a2ed3d4fb471dade_001full.jpg
Figure 2. Cross section looking west with conceptual drill targets and schematic drillhole traces. Assays from Riverside's sampling of rock dump materials from the two mine areas are labeled in black. Red areas are interpreted as manto and chimney target bodies that are now well defined and drill ready. Assays shown on figures 1 and 2 have been previously released and disclosed as summarized below the geochemical QA/QC and in published NI 43-101 Report that Questcorp published 2025 on Sedar+.
To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/10197/261433_a2ed3d4fb471dade_002full.jpg
The La Union Project
The La Union Project is a carbonate replacement deposit ("CRD") project hosted by Neoproterozoic sedimentary rocks (limestones, dolomites, and siliciclastic sediments) overlying crystalline Paleoproterozoic rocks of the Caborca Terrane. The structural setting features high-angle normal faults and low-to-medium-angle thrust faults that sometimes served as mineralization conduits. Mineralization occurs as polymetallic veins, replacement zones (mantos, chimneys), and shear zones with high-grade metal content, as shown in highlight grades of 59.4 grams per metric tonne (g/t) gold, 833 g/t silver, 11% zinc, 5.5% lead, 2.2% copper, along with significant hematite and manganese oxides, consistent with a CRD model (see the technical report entitled "NI 43-101 Technical Report on the Union Project, State of Sonora, Mexico" dated effective May 6, 2025 available under Questcorp's SEDAR+ profile). These targets also demonstrate intriguing potential for large gold discoveries potentially above an even larger porphyry Cu district potential as the Company's target concept at this time.
Questcorp cautions investors that grab samples are selective by nature and not necessarily indicative of similar mineralization on the property.
The technical and scientific information in this news release has been reviewed and approved by R. Tim Henneberry, P. Geo (BC), a director of the Company and a "qualified person" under National Instrument 43-101 - Standards of Disclosure for Mineral Projects.
About Questcorp Mining Inc.
Questcorp Mining Inc. is engaged in the business of the acquisition and exploration of mineral properties in North America, with the objective of locating and developing economic precious and base metals properties of merit. The Company holds an option to acquire an undivided 100% interest in and to mineral claims totaling 1,168.09 hectares comprising the North Island Copper Property, on Vancouver Island, British Columbia, subject to a royalty obligation. The Company also holds an option to acquire an undivided 100% interest in and to mineral claims totaling 2,520.2 hectares comprising the La Union Project located in Sonora, Mexico, subject to a royalty obligation.
Contact Information
Questcorp Mining Corp.
Saf Dhillon, President & CEO
This news release includes certain "forward-looking statements" under applicable Canadian securities legislation. Forward-looking statements include, but are not limited to, statements with respect to Riverside's arrangements with geophysical contractors to undertake orientation surveys and follow up detailed survey to confirm and enhance the drill targets. Forward-looking statements are necessarily based upon a number of estimates and assumptions that, while considered reasonable, are subject to known and unknown risks, uncertainties, and other factors which may cause the actual results and future events to differ materially from those expressed or implied by such forward-looking statements. Such factors include but are not limited to: the ability of Riverside to secure geophysical contractors to undertake orientation surveys and follow up detailed survey to confirm and enhance the drill targets as contemplated or at all, general business, economic, competitive, political and social uncertainties, uncertain capital markets; and delay or failure to receive board or regulatory approvals. There can be no assurance that the geophysical surveys will be completed as contemplated or at all and that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. The Company disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.
To view the source version of this press release, please visit https://www.newsfilecorp.com/release/261433
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