Potentially adding a further critical mineral and valuable by-product to a world-class lithium project

Highlights

• Wide, high-grade cesium pegmatite drill intercepts identified at the CV13 Pegmatite from assay overlimit analysis, including four (4) samples >20% Cs₂O. Results include:

Vega Zone

• 18.1 m at 2.71% Cs₂O, including 7.4 m at 5.45% Cs₂O (CV24-754).
• 11.1 m at 4.87% Cs₂O, including 7.1 m at 7.39% Cs₂O (CV24-520).
• 5.7 m at 4.97% Cs₂O, including 3.0 m at 8.20% Cs₂O (CV24-525).
• 9.6 m at 1.59% Cs₂O, including 4.4 m at 2.34% Cs₂O (CV24-579).
• 3.0 m at 9.43% Cs₂O, including 1.0 m at 22.41% Cs₂O (Channel CH23-069).

Rigel Zone

• 5.9 m at 11.19% Cs₂O, including 1.0 m at 22.69% Cs₂O (CV23-271).
• 5.0 m at 13.32% Cs₂O, including 2.0 m at 22.90% Cs₂O (CV23-255).
• 3.2 m at 10.24% Cs₂O, including 1.1 m at 26.61% Cs₂O (CV23-204).
• 4.5 m at 3.36% Cs₂O (CV23-198).

• The largest zone of cesium enrichment is coincident with the Company’s high-grade lithium Vega Zone (CV13) and can be traced through drilling over a very large area of ~600 m x 400 m ranging from 1-2 m to >10 m thick and remains open.
• The high-grade Rigel Zone, coincident with the apex of the structural flexure at CV13, is estimated through drilling to be at least ~200 m x 80 m in area and up to ~5 m thick.
• Mineralized cesium intercepts at the CV5 Pegmatite include:
  • 10.4 m at 1.30% Cs₂O, including 4.0 m at 2.02% Cs₂O (CV23-117).
  • 9.0 m at 1.20% Cs₂O, including 1.5 m at 5.03% Cs₂O (CV24-651).
  • 7.5 m at 1.29% Cs₂O, including 1.5 m at 3.90% Cs₂O (CV24-404).
  • 2.0 m at 5.24% Cs₂O (CV23-219).
  • 0.8 m at 13.04% Cs₂O (CV24-627).
• Results are highly encouraging as cesium is a high-value commodity due to its rarity and specialized applications.
  • Economically viable cesium deposits are very rare globally, but high value, and typically on a smaller scale of <10 kt to 350,000 kt in size and supported by drill intercepts of typically less than 3 to 10 m. This compares to lithium pegmatite deposits that typically range in the millions of tonnes (<10 Mt and rarely over 100 Mt) in size and are supported by much thicker drill intercepts.

Darren L. Smith, Patriot Executive and Vice President of Exploration, comments: “With the receipt of overlimit assay results, we have now confirmed a large cesium discovery at Shaakichiuwaanaan, supported by wide and well-mineralized drill intercepts. Cesium mineralization of this scale and grade, often combined with high-grade lithium and tantalum, is exceptionally rare globally and underscores the extraordinary endowment of the mineral system at Shaakichiuwaanaan in high-value critical minerals.

While our primary focus remains steadfast on advancing the CV5 Deposit to production based on its world-class lithium endowment, the discovery of cesium presents a compelling value-add opportunity for the Company. Cesium is a high-value and rare commodity which has the potential to become a meaningful by-product to future lithium operations, complementing our core business.”

“Given the strategic importance and scarcity of cesium in global markets – and its growing use in key industrial and specialized applications – this discovery has the potential to significantly enhance stakeholder value and re-affirms Shaakichiuwaanaan as one of the top LCT pegmatite assets in the world. For this reason, the Company intends to further evaluate the cesium opportunity as we advance Shaakichiuwaanan towards development,” added Mr. Smith.

Patriot Battery Metals Inc.  (TSX: PMET) (ASX: PMT) (OTCQX: PMETF) (FSE: R9GA) is pleased to announce the results of cesium (Cs) assay overlimit analysis, which reaffirm the discovery of two distinct zones of cesium mineralization at the CV13 Pegmatite. The CV13 Pegmatite forms part of the Company’s 100% owned Shaakichiuwaanaan Property (the “Property” or “Project”), located in the Eeyou Istchee James Bay region of Quebec.

The Shaakichiuwaanaan Property hosts a consolidated Mineral Resource Estimate[1] (“MRE”) of 80.1 Mt at 1.44% Li₂O Indicated and 62.5 Mt at 1.31% Li₂O Inferred. The CV5 Spodumene Pegmatite, which forms the bulk of the MRE, is accessible year-round by all-season road and is situated approximately 14 km from a major hydroelectric powerline corridor. The CV13 Pegmatite is located <3 km along geological trend from the CV5 Pegmatite, and hosts additional lithium and tantalum resources, as well as recently discovered zones of cesium mineralisation (see news release dated March 2, 2025).

CV13 Pegmatite

The initial discovery of two (2) distinct zones of cesium enrichment at CV13 was first announced in the Company’s news release dated March 2, 2025, and was based on drill hole pegmatite intercepts which had returned analytical results for cesium that exceeded the detection limit – >10,000 ppm Cs (i.e., >1% Cs or >1.06% Cs₂O) – of the analytical package. With the overlimit analytical results now received, the final grade-width calculations for the intervals >1% Cs₂O are reported in this news release (see Figure 1, Figure 2, Figure 3, Figure 4, Table 1, and Table 3).

Significant results at CV13 include:

Vega Zone

• 18.1 m at 2.71% Cs₂O, including 7.4 m at 5.45% Cs₂O (CV24-754).
• 11.1 m at 4.87% Cs₂O, including 7.1 m at 7.39% Cs₂O (CV24-520).
• 5.7 m at 4.97% Cs₂O, including 3.0 m at 8.20% Cs₂O (CV24-525).
• 9.6 m at 1.59% Cs₂O, including 4.4 m at 2.34% Cs₂O (CV24-579).
• 3.0 m at 9.43% Cs₂O, including 1.0 m at 22.41% Cs₂O (Channel CH23-069).

The largest of the two (2) cesium zones at CV13 is coincident with the high-grade (lithium) Vega Zone (Figure 1) and can be traced through drilling over an extensive area of ~600 m x 400 m, ranging in thickness from 1-2 m to >10 m. The cesium mineralization at the Vega Zone sits ~125 m to 150 m from surface and remains open to the northwest. Additionally, the cesium zone at Vega is commonly accompanied by high-grade lithium and tantalum (Table 1).

Rigel Zone

• 5.9 m at 11.19% Cs₂O, including 1.0 m at 22.69% Cs₂O (CV23-271).
• 5.0 m at 13.32% Cs₂O, including 2.0 m at 22.90% Cs₂O (CV23-255).
• 3.2 m at 10.24% Cs₂O, including 1.1 m at 26.61% Cs₂O (CV23-204).
• 4.5 m at 3.36% Cs₂O (CV23-198).

The newly named “Rigel Zone” is situated coincident with the apex of the structural flexure at CV13 and is estimated through drilling to have a high-grade footprint of approximately 200 m x 80 m at up to ~5 m thick. This zone includes the highest cesium grades reported to date from the Property – 1.1 m at 26.61% Cs₂O (CV23-204) and 2.0 m at 22.90% Cs₂O (CV23-255) – which imply intervals of near-massive pollucite and represent some of the highest known cesium grades reported globally in recent years.

The Rigel Zone is present at shallow depth (~50 m from surface) and, while it appears to be smaller in scale than the Vega Zone, it also appears to be higher grade. Additionally, similar to Vega, the cesium zone at Rigel may be accompanied by high-grade lithium and tantalum (Table 1).

Figure 1: Drill hole analytical result highlights for cesium from the Vega and Rigel zones at the CV13 Pegmatite.

Figure 2: Pollucite in grey quartz matrix from 139.3 m to 139.5 m in drill hole CV24-520 (Vega Zone), within a wider zone of cesium mineralization grading 7.39% Cs₂O over 7.1 m.

Figure 3: High-grade pollucite mineralization in drill hole CV23-271 (Rigel Zone) grading 22.69% Cs₂O over 1.0 m (64.0 m to 65.0 m).

Figure 4: Semi-massive to massive pollucite intercept (red box) in drill hole CV23-255 (Rigel Zone) grading 17.95% Cs₂O over 3.7 m (76.3 m to 80.0 m), including 22.90% Cs₂O over 2.0 m (78.0 m to 80.0 m).

CV5 Pegmatite

In addition to CV13, the CV5 Pegmatite also returned multiple cesium mineralized intercepts (see Figure 5, Figure 6, Figure 7, Table 2, and Table 3). Initial review indicates a wider distribution of cesium across the pegmatite, with distinct zones less apparent compared to the Vega and Rigel cesium zones at the CV13 Pegmatite. However, given the density of drilling, further review and modelling is required to determine continuity and distinct zonation, especially given that cesium zones are relatively small but very high-value. Drill intercept highlights for cesium at CV5 include:

• 4 m at 1.30% Cs₂O, including 4.0 m at 2.02% Cs₂O (CV23-117).
• 0 m at 1.20% Cs₂O, including 1.5 m at 5.03% Cs₂O (CV24-651).
• 5 m at 1.29% Cs₂O, including 1.5 m at 3.90% Cs₂O (CV24-404).
• 0 m at 5.24% Cs₂O (CV23-219).
• 8 m at 13.04% Cs₂O (CV24-627).

Figure 5: Pollucite mineralization in drill hole CV23-219 (CV5) grading 5.24% Cs₂O over 2.0 m (109.5 m to 111.5 m).

Figure 6: Drill hole analytical result highlights for cesium at the CV5 Pegmatite.

Figure 7: Pollucite mineralization in drill hole CV24-651 (CV5) grading 5.03% Cs₂O over 1.5 m (61.0 m to 62.5 m).

Table 1: Cesium assay summary for drill holes at the CV13 Pegmatite (Vega and Rigel Zones).

Table 2: Cesium assay summary for drill holes at the CV5 Pegmatite.

Mineralogy and Geological Modelling

Pollucite, the principal and preferred ore mineral for cesium, has been identified by XRD mineralogical analysis at Shaakichiuwaanaan and is interpreted to be the primary source of the cesium enrichment at the Property based on cesium grades and logging. The high-grade cesium intercepts indicate that semi-massive to massive pollucite is present, especially in the Rigel Zone where several 10% to 20+% Cs₂O intercepts are present. A mineralogical program focused on the Vega and Rigel cesium zones is underway to confirm the presence and quantitative abundance of pollucite, and to a lesser extent lepidolite where present.

With the overlimit assays for cesium now received, the Company is actively geologically modelling the Vega and Rigel cesium zones, both within the wider pegmatite geological model. Additionally, cesium will be added to the block model to further assess the potential of each zone.

In the same way that the Company’s tantalum resource has the potential to be a valuable by-product, the identification of significant cesium mineralization at CV13 presents an opportunity to further evaluate the potential of cesium as a marketable by-product, which could complement the Company’s lithium-focused development strategy and add to the suite of critical minerals that could be produced at Shaakichiuwaanaan. As the Feasibility Study for CV5 progresses for its lithium operation, the Company will assess the potential for a cesium resource at Shaakichiuwaanaan and its implications for future exploration and development.

About Cesium – extremely rare critical metal

Cesium (Cs) is a specialty metal and is listed as a critical and strategic mineral by Canada, the province of Quebec (Canada), Japan, and the United States. The principal use of cesium, which is almost exclusively recovered (in its primary form) from the mineral pollucite, is in the form of cesium formate brine. Due to its high-density, low toxicity, biodegradable nature, and recoverability, cesium is used to support the completion of oil and gas wells at high pressure and temperature.

Cesium is also used in atomic clocks, GPS, aircraft guidance, and telecommunications. Its compounds have various applications: cesium carbonate in fuel cells, cesium chloride in chemistry and nuclear medicine, cesium hydroxide in batteries, cesium iodide in X-ray equipment, cesium nitrate in pyrotechnics and scintillation counters, and cesium sulfates in water treatment and scientific instruments. Cesium pricing varies based on its end-product form and purity; however, in its refined form, cesium metal (Cs >99.5%) is a high value commodity similar to gold and currently trades around US$2,550/oz (excluding VAT, Source – Shanghai Metal Markets).

Mineral deposits of cesium (pollucite) are extremely rare globally and represent the most fractionated component of LCT pegmatite systems, which are effectively the only primary source of cesium globally. Economic deposits of cesium are typically on the scale of <10 kt to 350,000 kt in size and supported by drill intercepts of typically less than 3 to 10 m (core length). This compares to lithium pegmatite deposits that typically range in the millions of tonnes (<10 Mt and rarely over 100 Mt) in size and are supported by much thicker drill intercepts.

Examples of the few current/past producing mines include Tanco (Canada), Bikita (Zimbabwe), and Sinclair (Australia). Australia’s first commercial cesium mine, Sinclair, extracted its last cesium in 2019.

Table 3: Attributes for drill holes discussed herein.

Quality Assurance / Quality Control

A Quality Assurance / Quality Control protocol following industry best practices was incorporated into the program and included systematic insertion of quartz blanks and certified reference materials (Li focus) into sample batches at a rate of approximately 5% each. Additionally, analysis of pulp-split sample duplicates was completed to assess analytical precision, and external (secondary) laboratory pulp-split duplicates were prepared at the primary lab for subsequent check analysis and validation.

All samples collected were shipped to SGS Canada’s laboratory in Val-d’Or, QC, or Radisson, QC, for sample preparation (code PRP90 special) which includes drying at 105°C, crush to 90% passing 2 mm, riffle split 250 g, and pulverize 85% passing 75 microns. The pulps were shipped by air to SGS Canada’s laboratory in Burnaby, BC, where the samples were homogenized and subsequently analyzed for multi-element (including Li, Cs, and Ta) using sodium peroxide fusion with ICP-AES/MS finish (codes GE_ICP91A50 and GE_IMS91A50).

Overlimits for cesium are requested when the analytical result exceeds the upper detection limit (10,000 ppm Cs) of the GE_ICP91A50 and GE_IMS91A50 analytical packages. The overlimit package used for cesium is either GC_AAS49C – acid digestion for alkaline elements or GC_XRF76V – borate fusion XRF. Both cesium overlimit packages report Cs in %.

Qualified/Competent Person

The information in this news release that relates to exploration results for the Shaakichiuwaanaan Property is based on, and fairly represents, information compiled by Mr. Darren L. Smith, M.Sc., P.Geo., who is a Qualified Person as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects, and member in good standing with the Ordre des Géologues du Québec (Geologist Permit number 01968), and with the Association of Professional Engineers and Geoscientists of Alberta (member number 87868). Mr. Smith has reviewed and approved the technical information in this news release.

Mr. Smith is an Executive and Vice President of Exploration for Patriot Battery Metals Inc. and holds common shares, Restricted Share Units (RSUs), and Performance Share Units (PSUs) in the Company.

Mr. Smith has sufficient experience, which is relevant to the style of mineralization, type of deposit under consideration, and to the activities being undertaken to qualify as a Competent Person as described by the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code). Mr. Smith consents to the inclusion in this news release of the matters based on his information in the form and context in which it appears.

About Patriot Battery Metals Inc.

Patriot Battery Metals Inc. is a hard-rock lithium exploration company focused on advancing its district-scale 100%-owned Shaakichiuwaanaan Property (formerly known as Corvette) located in the Eeyou Istchee James Bay region of Quebec, Canada, which is accessible year-round by all-season road and is proximal to regional powerline infrastructure. The Shaakichiuwaanaan Mineral Resource¹, which includes the CV5 & CV13 spodumene pegmatites, totals 80.1 Mt at 1.44% Li₂O Indicated, and 62.5 Mt at 1.31% Li₂O Inferred, and ranks as the largest lithium pegmatite resource in the Americas, and the 8^th largest lithium pegmatite resource in the world.

A Preliminary Economic Assessment (“PEA”) was announced for the CV5 Pegmatite August 21, 2024, and highlights it as a potential North American lithium raw materials powerhouse. The PEA outlines the potential for a competitive and globally significant high-grade lithium project targeting up to ~800 ktpa spodumene concentrate using a simple Dense Media Separation (“DMS”) only process flowsheet.

¹ Shaakichiuwaanaan (CV5 & CV13) Mineral Resource Estimate (80.1 Mt at 1.44% Li₂O and 163 ppm Ta₂O₅Indicated, and 62.5 Mt at 1.31% Li₂O and 147 ppm Ta₂O₅ Inferred) is reported at a cut-off grade of 0.40% Li₂O (open-pit), 0.60% Li₂O (underground CV5), and 0.80% Li₂O (underground CV13) with an Effective Date of August 21, 2024 (through drill hole CV24-526). Mineral Resources are not Mineral Reserves as they do not have demonstrated economic viability.