Mineral Resource update includes maiden estimates at the Helios Caesium Zone and CV4 Pegmatite, contributing to overall resource growth in all three critical minerals (Li, Cs, Ta) at the Shaakichiuwaanaan Property

MONTREAL, Nov. 3, 2026 /PRNewswire/ -- November 4, 2026 â Sydney, Australia

Significant increase in contained caesium metal (55%), grade (31%), and tonnage (18%) of the Caesium Zone MRE1, inclusive of the Vega, Rigel, and newly estimated Helios Zones.

1,844,000 t at 4.40% Cs2O (Indicated) â 81,200 t Cs2O in contained metal.

981,000 t at 3.00% Cs2O (Inferred) â 29,400 t Cs2O in contained metal.

Already the world's largest pollucite (caesium) pegmatite, this MRE has further increased contained metal from 71,000 t to 110,600 t Cs2O.

Additional critical mineral added to resource base with maiden rubidium (Rb) resources declared within the Caesium Zone MRE at a grade of 0.46% Rb2O (Indicated) and 0.37% Rb2O (Inferred). Rubidium is a soft, silvery-white alkali metal used primarily in scientific research, precision timekeeping, and specialized technologies.

Consolidated MRE at Shaakichiuwaanaan confirms over 40 Mt of greater than 2% Li2O grade at CV5 and CV13 combined (indicated).

Sensitivity analysis outlines very high-grade (Li) subsets of the resource at significant tonnage, primarily reflecting the Nova (CV5) and Vega (CV13) Zones, respectively (at 1.5% Li2O cut-off):

36.5 Mt at 2.04% Li2O (Indicated), 4.1Mt at 2.01% Li2O (Inferred).

5.9 Mt at 2.77% Li2O (Indicated), 4.2Mt at 2.24% Li2O (Inferred).

113.9 Mt at 1.43% Li2O and 164 ppm Ta2O5 (Indicated) â 4.03 Mt LCE.

33.8 Mt at 1.24% Li2O and 150 ppm Ta2O5 (Inferred) â 1.03 Mt LCE.

MRE continues to re-affirm Shaakichiuwaanaan as one of the largest and highest-grade tantalum pegmatites globally.

Increase in contained LCE2 (5%) driven by combined impact of improved tonnage (4%) and grade (0.2%) of consolidated MRE at Shaakichiuwaanaan3:

A total of 87.4 Mt (Indicated) and 2.2 Mt (Inferred) is contained within a single dyke at the CV5 Pegmatite, which is anticipated to significantly limit external dilution and simplify mining.

Includes 1.75 Mt at 1.24% Li2O (Inferred) maiden resource at the CV4 Pegmatite, approximately 1.5 km along strike and to the east of CV5, with the gap between offering further exploration potential for additional resource growth (more drilling required).

MRE4 update announced herein to underpin an updated Feasibility Study for Li and Ta on the CV5 Pegmatite and a Preliminary Economic Assessment for Li, Cs, and Ta on the broader Project (CV5 & CV13 Pegmatites), on schedule to be announced before year end.

Darren L. Smith â Executive Vice President of Exploration commented: "Although the 2025 drill program focused on development objectives for the Project, the work has also grown the overall resource base for all three metals, highlighted by the significant increases in the Caesium Zone MRE grade, tonnage, and contained metal.

"Shaakichiuwaanaan continues to demonstrate considerable scale in lithium, caesium, and tantalum inclusive of very high-grade subsets of the resource. Given the size of the overall resource, it is easy to forget that the scale and grade of the Nova and Vega Zones are globally significant in their own right. This is an important part of what makes the Project so unique. We are very confident there is a lot more to discover as we expand our exploration focus in future programs," added Mr. Smith.

PMET RESOURCES INC. (THE "COMPANY" OR "PMET") (TSX: PMET) (ASX: PMT) (OTCQX: PMETF) (FSE: R9GA) is pleased to announce an updated Consolidated Mineral Resource Estimate ("Consolidated MRE") for its 100%-owned Shaakichiuwaanaan Property (the "Property" or "Project") located in the Eeyou Istchee James Bay region of Quebec. The Consolidated MRE, the fifth to date for the Project ("MRE-5"), includes the CV5, CV13, and CV4 lithium-caesium-tantalum ("LCT") pegmatites and is accessible by all-season road, proximal to regional hydropower infrastructure (Figure 2 and Figure 14).

In addition to continued growth in the lithium-tantalum consolidated resource base (see below), MRE-55 has resulted in a significant increase in caesium ("Cs") resources both in terms of grade (31%), tonnage (18%), and contained metal (55%) inclusive of the Vega, Rigel, and newly estimated Helios zones (all within the CV13 Pegmatite) â 1,844,000 t at 4.40% Cs2O (Indicated) and 981,000 t at 3.00% Cs2O (Inferred) for a contained caesium content (Cs2O) of 81,200 t and 29,400 t, respectively (Table 2). This reaffirms Shaakichiuwaanaan's position as hosting the world's largest pollucite (caesium) pegmatite MRE (Figure 1).

The scale of Shaakichiuwaanaan's caesium resource is particularly significant given the supply-constrained nature of the global caesium market. Caesium formate is a premium high-density drilling fluid used in high-pressure, high-temperature (HPHT) oil and gas wells, particularly in the North Sea, with potential for broader adoption in offshore basins such as Brazil, the Gulf of Mexico, and Southeast Asia. Historically limited and highly concentrated supply has constrained wider market adoption. The emergence of a large-scale, reliable North American source of caesium could not only diversify global supply chains, but also enable the development of new caesium formate inventory pools, supporting expanded offshore exploration and greater energy security.

Additionally, a maiden rubidium ("Rb") Mineral Resource has been declared within the Caesium Zone MRE at a grade of 0.46% Rb2O (Indicated) and 0.37% Rb2O (Inferred). The target mineral for recovery for both Cs and rubidium Rb is pollucite, which is the primary host to Cs at Shaakichiuwaanaan and is the preferred source mineral for Cs globally.

The updated Consolidated MRE demonstrates continued growth in the overall resource base with increases in lithium grade (0.2%), tonnage (4%), and contained metal (5%). This includes tonnage increases at both CV5 (1.6%) and CV13 (10.4%) (Table 1):

113.9 Mt at 1.43% Li2O and 164 ppm Ta2O5 (Indicated) â 4.03 Mt LCE and 18.7 kt Ta2O5 contained, respectively.

33.8 Mt at 1.24% Li2O and 150 ppm Ta2O5 (Inferred) â 1.03 Mt LCE and 5.1 kt Ta2O5 contained, respectively.

Shaakichiuwaanaan continues to host one of the world's largest and highest-grade tantalum pegmatite MREs. Coupled with the scale and grade of the lithium and caesium resources, the tantalum provides another key differentiator for the Project.

A total of 87.4 Mt (Indicated) and 2.2 Mt (Inferred) is contained within a single principal dyke at the CV5 Pegmatite, which extends nearly 5 km in length at true widths of up to ~125 m. The scale of the resources within this single, broad dyke is significant as it is anticipated to reduce external dilution, simplify the overall mining approach, and reduce the mineral processing risk.

Additionally, MRE-5 includes maiden resources at the CV4 Pegmatite totaling 1.75 Mt at 1.24% Li2O (Inferred) and is interpreted to represent a potential 1.5 km extension of the principal CV5 Pegmatite dyke. This gap (CV5 to CV4) represents a key exploration area for future resource growth.

HIGH-GRADE NOVA AND VEGA ZONES ARE KEY DIFFERENTIATORS

The relatively high-grade nature of the Shaakichiuwaanaan MRE, highlighted by the Nova (CV5) and Vega (CV13) Zones, is a key and powerful differentiator for the Company (Figure 5). In the MRE-5 sensitivity analysis (Table 3), significant tonnage is outlined at very high-grade (>2.00% Li2O), primarily reflecting these two zones, respectively (at 1.5% Li2O cut-off):

36.5 Mt at 2.04% Li2O (Indicated), 4.1Mt at 2.01% Li2O (Inferred).

5.9 Mt at 2.77% Li2O (Indicated), 4.2Mt at 2.24% Li2O (Inferred).

These zones of intense spodumene mineralization at scale (both with 10+ m drill intervals at >5% Li2O) are exceedingly rare â and potentially unique â in LCT pegmatite deposits known globally. Such scale and grade offer the opportunity to have higher-margin tonnes (potentially relatively early in the mine-life), improved recoveries, and backstop a highly robust production profile that can withstand significant downturn in the markets over prolonged periods. Collectively, these attributes lend Shaakichiuwaanaan a very defensible nature to market nuance, which is anticipated to be outlined in further detail within the updated Feasibility Study at CV5 and Preliminary Economic Assessment on the broader project (CV5 & CV13) scheduled to be announced before year end.

NEXT STEPS

MRE-5 â which includes drilling through to the end 2025 â is intended to underpin an updated Feasibility Study for Li and Ta on the CV5 Pegmatite and a Preliminary Economic Assessment for Li, Cs, and Ta on the broader Project (CV5 & CV13 Pegmatites), on schedule to be announced before year end. Drilling completed in 2026 will be incorporated into a future MRE update for the Project, anticipated in 2027.

MINERAL RESOURCE STATEMENT (NI 43-101) â MRE-5

Table 1: Consolidated Mineral Resource Statement for the Shaakichiuwaanaan Project.

Table 2: Caesium Zone Mineral Resources within the CV13 Pegmatite.

Mineral Resources were prepared in accordance with National Instrument 43-101 â Standards for Disclosure for Mineral Projects ("NI 43-101"), the CIM Definition Standards (2014) and the JORC Code (2012). Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. This estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical, marketing, economic, or other relevant issues.

The independent Competent Person (CP), as defined under JORC, and Qualified Person (QP), as defined by NI 43â101 for this resource estimate is Todd McCracken, P.Geo., Director â Mining & Geology â Central Canada, BBA Consultants. The Effective Date of the estimate is July 10, 2026 (through drill hole CV25-1025).