Sendero Resources Rebuilds Penas Negras Drill Assay Database, Applying Consistent CuEq Methodology Across 77 Historical Holes
Sendero restates sub-economic copper as 0.57% CuEq on 100% recovery.
Sendero Resources Corp. (SEND) has announced a review and recalculation of metal equivalents for historical drilling data at its Peñas Negras copper-gold project in La Rioja, Argentina. The company rebuilt its database from historical programs conducted by prior owners and operators, incorporating 77 holes and 6,433 assay samples. No new holes were drilled and no new assays were taken for this update.
The analysis converted metal equivalents from a previous gold-equivalent (AuEq) basis to a copper-equivalent (CuEq) basis, applied uniformly across the entire historical dataset. The disclosed CuEq methodology utilized metal prices of US$4.50/lb for copper, US$3,375/oz for gold, US$60/oz for silver, US$25/lb for molybdenum, US$1,440/t for lead, and US$2,940/t for zinc. The calculation assumed 100% recoveries for all metals. Sendero noted that the reported intercepts represent downhole, or drill-indicated, lengths and that there is insufficient data to determine true thickness.
Key intercepts reported by the company include:
- PNDH-06: 236.1 m @ 0.57% CuEq from 31.9 m (including 44.2 m @ 1.23% CuEq, including 24 m @ 1.53% CuEq)
- PNDH-03: 268 m @ 0.49% CuEq (including 62 m @ 0.66% CuEq)
- PNDH-04: 266 m @ 0.48% CuEq (including 52 m @ 0.61% CuEq)
- PND-02: 208.4 m @ 0.56% CuEq (including 43.6 m @ 1.0% CuEq)
- PNR-33: 188 m @ 0.46% CuEq
- PNR-23: 196 m @ 0.44% CuEq
- PNDH-05: 194 m @ 0.4% CuEq
- PNR-30: 161 m @ 0.54% CuEq (including 18 m @ 1.26% CuEq)
- PNR-28: 102 m @ 0.93% CuEq (including 32 m @ 1.95% CuEq, including 2 m @ 23.15% CuEq)
- PNR-03: 68 m @ 1.15% CuEq (including 52 m @ 1.26% CuEq)
- PNDH-01: 194 m @ 0.2% CuEq
- PNR-29: 150 m @ 0.27% CuEq
- PNDH-02: 76 m @ 0.29% CuEq
The technical information was prepared by Qualified Person Steven McMullan, P.Geo. Jeremy Gillis, Interim CEO, provided commentary on the findings.
Sendero Resources Corp. (SEND) released a database recompilation and equivalent-metal rebranding rather than new drill results. The update introduces no new rock, assays, resources, metallurgy, or economics. The change involves shifting the equivalent basis from AuEq to CuEq and using a shorter recomposited length for PNDH-06, neither of which adds metal. Historical intercepts were already public as of February 2026.
The company remains a pre-resource explorer and micro-cap with a market capitalization of approximately C$18.6 million. An August 17, 2026 reconnaissance program consisting of three holes totaling 396.3 meters, with a best intercept of 1.04 g/t Au over 1.5 meters, was viewed as a disappointment. The equity fell from approximately C$1.17 on August 14 to C$0.65 on August 31.
The stock has round-tripped approximately 65% from its C$2.00 January peak and is currently near its 52-week low. The release re-presents previously demonstrated data without improving grade or width substance. Sendero’s primary challenge remains a thin, low-grade, unaudited historical dataset with sub-economic primary copper, which this release does not address.
Sendero Resources Corp. (TSXV: SEND, FSE: 9O40) is a copper-gold explorer operating the Peñas Negras project in the Vicuña belt of Argentina’s La Rioja and San Juan provinces. The company holds a 100% interest in 120 km² of land at Peñas Negras, with an option to earn a further 100% of eight additional concessions totaling 91.7 km², bringing the total project area to 211.77 km². The property is located approximately 18 km southeast of Lundin’s Caserones, 24 km northeast of NGEx’s Lunahuasi, 32 km north-northeast of the BHP-Lundin Filo del Sol project, and 12 km north-northeast of the Josemaria resource area.
The project is currently in the exploration stage, with no established resource, reserve, or economic study on Peñas Negras. Historic drilling has totaled approximately 15,875 meters across roughly 80 holes, conducted by Eldorado, Anglo American, and Sendero in 2024. The company’s leadership includes Interim CEO Jeremy Gillis, Director and Qualified Person Steven McMullan, P.Geo., and CFO Dave Cross. Key backers include Peter Marrone, Pat DiCapo, and Eduardo Elsztain, according to the company’s May 2026 investor deck.
The capital structure, as outlined in the May 2026 deck, consists of approximately 26.5 million shares, 12.1 million warrants, and 2.5 million options.