North American Niobium Reports Strong Niobium and Copper Mineralization at Seigneurie Project, Québec with 842.3 ppm Nb2O5 Over 10m

Detailed Assay Findings from Seigneurie Drill Hole SGN-2026-007

On July 21, 2026, NIOB announced that drill hole SGN-2026-007 at the Seigneurie Project has provided a comprehensive mineralization profile, with final assays confirming significant niobium oxide grades across two separate intervals. The main niobium zone extends 10 metres averaging 842.3 ppm Nb2O5, while a secondary zone measures 7.3 metres averaging 453 ppm Nb2O5. These grades align with those from hole SGN-2026-003 reported on July 3, 2026, but cover more than double the interval length, indicating a potentially larger mineralized area.

Composite niobium oxide intervals were calculated using length-weighted averages applying a 400 ppm Nb2O5 cutoff, with interval boundaries set at or above this cutoff and allowing up to 4 metres of internal dilution. Niobium oxide values were derived from elemental laboratory assays using standard stoichiometric conversions. The reported intervals represent core (downhole) lengths; true widths will be determined as geological understanding advances.

Unexpected Copper Mineralization and Deeper Zones

In addition to niobium zones, hole SGN-2026-007 intersected an unanticipated copper interval at greater depth. This copper zone spans 3 metres (216.5–219.5 m) with an average grade of 2,701.7 ppm copper, nearly three times higher than copper grades from the previously reported hole SGN-2026-003. This suggests the Seigneurie pegmatite system may contain multiple mineralized horizons with distinct metal assemblages, potentially broadening the project's economic scope.

The copper mineralization is concentrated near the pegmatite contact with amphibolite rocks, indicating a geological setting conducive to copper enrichment. Copper assays were conducted by SGS Canada Inc. in Val-d'Or, Québec, using sodium-peroxide-fusion, nitric acid, ICP-AES methods at an ISO/IEC 17025-accredited facility. The economic significance of the copper relative to niobium and rare earth targets remains under evaluation.

Geological Context and Pegmatite Features

The Seigneurie Project lies within Québec's Grenville Province, a region known for hosting various rare earth element and critical mineral deposits. Hole SGN-2026-007 represents the first systematic drill targeting rare earths or niobium within the Seigneurie pegmatite system. The hole was drilled at coordinates 481680E/5382081N (UTM NAD83 Zone 18), with an azimuth of 0° and dip of 45°, reaching approximately 290 metres depth.

This hole intersected about 105.45 metres of pink-to-red, K-feldspar-rich pegmatite containing 15–20% smoky quartz and titanium-magnetite. Handheld radiometric readings within the pegmatite reached roughly 1,400 counts per second, noted as indicative but not grade measurements. Core recovery averaged about 90% through mineralized zones, ensuring reliable sample representation and demonstrating strong technical control over drilling and sampling.

Correlation with Rare Earth Element Intervals

The niobium oxide intervals in hole SGN-2026-007 correspond to dysprosium oxide and heavy rare earth element (HREO) zones previously disclosed in the July 3, 2026 news release. Management suggests a probable correlation between niobium and yttrium, the dominant HREO element, pending confirmation from upcoming mineralogical analyses. This spatial association indicates the pegmatite may host integrated critical mineral assemblages relevant to energy and defense sectors.

Located approximately 950 metres west of the higher-grade hole SGN-2026-003, SGN-2026-007’s results enhance the company’s understanding of mineralization distribution across the Seigneurie pegmatite system. Mapping the spatial and grade variability of niobium and rare earth elements is key to assessing economic potential and guiding future drilling priorities.

Analytical Procedures and Quality Control

Samples from SGN-2026-007 were analyzed by SGS Canada Inc. Rare earth elements were measured using sodium-peroxide-fusion ICP-MS (method GE_IMS91A50), niobium by fused-bead XRF (GO_XRF72NB), and copper via sodium-peroxide-fusion, nitric acid, ICP-AES (GE_ICP91A50). The company disclosed these protocols to ensure transparency in assay reporting.

Quality assurance included insertion of certified reference materials, blanks, and field duplicates comprising about 13% of samples. Samples consisted of NQ-size half-core sections split longitudinally and sampled over 0.5 to 1.0 metre intervals, with remaining half-core retained for reference. Approximately 5% of QA/QC samples were still under review at announcement time. No verification limitations were found during the Qualified Person’s assessment of SGS certificates and quality-control data.

Next Steps: Mineralogical Analysis for Economic Evaluation

NIOB plans to conduct automated mineralogy (TIMA) studies to identify mineral hosts and deportment of rare earth elements and niobium within the pegmatite. CEO Murray Nye emphasized that grade alone does not determine economic viability; understanding mineral distribution and processing characteristics is critical.

If TIMA analysis does not definitively identify REE-bearing minerals, follow-up laser ablation ICP-MS or electron microprobe analyses will be performed to provide elemental mapping at microscopic scales. These studies will guide target prioritization across the Québec portfolio and inform decisions on further drilling or metallurgical testing.

Expansive Exploration Strategy Across Québec Holdings

North American Niobium and Critical Minerals Corp. controls a district-scale land package totaling 29,936 hectares in Québec's Grenville Province, along with the Silver Lake property in British Columbia’s Omineca Mining Division. The Québec properties host documented rare earth element, niobium, and nickel-copper occurrences, positioning NIOB to explore multiple critical mineral targets over a broad region. Seigneurie Project results form a key component of the company’s strategy to develop assets relevant to energy and defense applications.

As results from the Seigneurie drill program are processed, NIOB intends to advance exploration across its Québec portfolio to prioritize the most prospective targets. Confirmed niobium and rare earth mineralization at Seigneurie, combined with the district-scale land position, supports evaluation of multiple mineralized horizons and pegmatite systems within the Grenville Province, an established critical mineral region.

Comparison with Prior Drill Hole SGN-2026-003

Results from SGN-2026-007 are compared with previously reported hole SGN-2026-003, located roughly 950 metres west. While niobium oxide grades are similar, SGN-2026-007’s mineralization extends over more than twice the length, suggesting a substantial areal extent and significant total metal content across the property.

The copper interval in SGN-2026-007, averaging 2,701.7 ppm over 3 metres, is nearly threefold higher than copper in SGN-2026-003. This compositional variation indicates geological complexity within the pegmatite system, warranting continued investigation and systematic sampling to delineate mineralization patterns.

Technical Compliance and Data Verification

The scientific and technical information complies with National Instrument 43-101 (NI 43-101) standards for mineral project disclosure in Canada. Clyde McMillan, P.Geo., a consultant and Qualified Person under NI 43-101, reviewed and approved the technical content, certifying that disclosures meet Canadian securities requirements.

The Qualified Person verified data by reviewing SGS analytical certificates and reconciling reported values with laboratory records and quality-control results. No limitations were identified. Core recovery averaged approximately 90% through mineralized intervals, not materially affecting sample representivity. This independent verification ensures transparency and reliability of the reported results for investors and stakeholders.