Sendero Resources Reports Drilling Results at Penas Negras Project; Confirms Geological Model and Identifies Geochemical Vectors in Vicuna Belt, Argentina

Sendero Resources Corp. (SEND) has completed its initial 2026 reconnaissance drilling program at its 100%-owned Peñas Negras project in La Rioja, Argentina. The company finished three diamond drillholes on the southwestern margin of the target area, totaling 396.3 meters: PNDH-200 (102.6 m), PNDH-201 (137.0 m), and PNDH-203 (156.7 m).

The most significant results came from Hole PNDH-201, which returned the following intercepts: - 1.04 g/t Au over 1.5 m from 14.0 m - 48 g/t Ag over 1.5 m from 14.0 m - 28.2 g/t Ag over 1.0 m from 57.0 m

These values are situated within a broader 46-meter interval from surface that averages 0.11 ppm Au. Hole PNDH-203 confirmed the presence of the Mogotes Fault and returned anomalous antimony values. While Hole PNDH-200 was completed, the release did not provide specific gold or silver intercepts for it.

In addition to drilling, the company reported 453 rock samples across the property. Results included up to 4.82 g/t Au and 18.00 g/t Ag in the PN-NNW area, located approximately 9 km north-northwest of the drilling. The PN-NW area, approximately 6.5 km north-northwest, yielded up to 1.65 g/t Au, while the southwest drilling area returned up to 5.13 g/t Ag.

Sendero Resources described the findings as validation of its porphyry-epithermal model, citing alteration, pathfinder elements including Sb, As, Cu, Mo, Pb, and Zn, stockwork veining, and an extensive leached cap. True widths are stated as unknown, and no cutoff grade was disclosed.

Sendero Resources Corp. (SEND) is an early-stage explorer with no revenue, no resource, and no mine, meaning drilling results remain the primary value driver. The company’s latest release is considered material due to the significant gap between prior market expectations and the results delivered.

Prior disclosures established an anchor for investor expectations. Phase 1 drilling included 364.2 m @ 0.51 g/t AuEq, or 185.7 gram-metres. Additionally, a February 17, 2026 release announced a fully funded 3,000–3,500 m, eight-hole program targeting the Mogotes fault.

Today’s release delivers only three reconnaissance holes totaling 396.3 m. The best drill interval reported is 1.5 m @ 1.04 g/t Au, or 1.56 gram-metres. The results include no porphyry copper grades and show no resource-scale continuity.

The results are materially weaker than the anchor previously provided to the market. The findings do not confirm economic mineralization, confirming only geological features. Sendero’s stock previously ran to $2.00 in January 2026, collapsed to $0.87 by July, and rebounded to $1.17 ahead of this result. The release fails to justify even the rebound level.

On a financial basis, the as-reported Q1-2026 balance sheet showed only C$196,049 in cash and C$1.799M in accounts payable. Subsequent December 2025 and January 2026 placements raised additional capital, but today’s release does not reconcile the “fully funded to continue diamond drilling” claim with current working capital or the actual 396 m delivered versus the previously announced 3,000–3,500 m program.

Sendero Resources Corp. (SEND) is a junior exploration company focused on copper-gold development at its Peñas Negras project, located in the Vicuña Belt across La Rioja and San Juan provinces in Argentina. The company holds a 100% interest in the project, which covers a total area of 211.77 km². Additionally, Sendero has an option to earn a further 100% interest in eight concessions covering 91.7 km². The property is situated near several major mining operations, including Lundin Mining’s Caserones mine, NGEx Minerals’ Lunahuasi project, and the BHP-Lundin Filo del Sol and Josemaría projects. No mineral resource or reserve has been defined for the project.

Historical exploration at Peñas Negras has been conducted by previous operators including Anglo American, Vale, Golden Arrow, Eldorado, and Solitario. Sendero maintains a database of approximately 15,875 meters of historic drilling across 80 holes. These historic intercepts include long, low-grade gold zones, such as 364.2 m @ 0.51 g/t AuEq, as well as narrow high-grade cores, such as 2 m @ 20.58 g/t Au.

Financially, the company reported as-reported cash of C$196,049 and accounts payable of C$1,799,281 for the first quarter of 2026, resulting in negative working capital. While subsequent placements in December 2025 and January 2026 raised additional funds, current cash balances were not provided in the latest release. The company has generated no revenue and reported negative operating cash flow.