World’s Largest Pollucite-Hosted Caesium Pegmatite Mineral Resource Defined at Shaakichiuwaanaan Rigel and Vega confirmed as a major caesium discovery with potential to be a significant supply source for global markets, including the next wave of terrestrial solar technologies
Patriot Battery Metals Inc.
Suite 900 - 1801, McGill College, Montreal, Qc, H3A 1Z4
www.patriotbatterymetals.com TSX: PMET / ASX: PMT / OTC: PMETF / FSE: R9GA
World’s Largest Pollucite-Hosted Caesium Pegmatite Mineral
Resource Defined at Shaakichiuwaanaan
Rigel and Vega confirmed as a major caesium discovery with potential to be a significant
supply source for global markets, including the next wave of terrestrial solar technologies
July 20, 2025 – Montreal, QC, Canada July 21, 2025 – Sydney, Australia
HIGHLIGHTS
• World’s largest pollucite-hosted caesium pegmatite deposit confirmed at the
Shaakichiuwaanaan Project , with a maiden Mineral Resource Estimate (“Caesium
Zone MRE”) of:
o Rigel Caesium Zone
▪ Indicated: 163,000 t at 10.25% Cs2O, 1.78% Li2O, and 646 ppm Ta2O5.
o Vega Caesium Zone
▪ Indicated: 530,000 t at 2.61% Cs2O, 2.23% Li2O, and 172 ppm Ta2O5.
▪ Inferred: 1,698,000 t at 2.40% Cs2O, 1.81% Li2O, and 245 ppm Ta2O5.
o Total contained caesium content of 30.5 kt Cs2O Indicated and 40.8 kt Cs 2O
Inferred, highlighting the scale and global significance of the discovery.
• Caesium resources in the Rigel and Vega zones are now included within the CV13
Pegmatite open-pit resource that forms part of the Company’s consolidated MRE for the
Project (including both the CV5 and CV13 pegmatites ) (“Consolidated MRE”) – that has
been updated and restated as follows:
o Indicated: 108.0 Mt at 1.40% Li2O, 0.11% Cs2O, 166 ppm Ta2O5, and 66 ppm Ga.
o Inferred: 33.4 Mt at 1.33% Li2O, 0.21% Cs2O, 155 ppm Ta2O5, and 65 ppm Ga.
• Caesium is a high-value, rare, and critical mineral which is currently supply constrained with
only limited sources supplying the global market1. A discovery of this size, grade, and scale
has the potential to be a primary source of supply for the global market, including new and
potentially growing applications in emerging next generation terrestrial solar panel
applications where caesium has been found to play a vital role in significantly improving
panel efficiency, stability, and life span.
1 Mineral deposits of pollucite-hosted caesium are extremely rare globally and represent the most fractionated component of LCT
pegmatite systems, which are effectively the only primary and economic source of caesium globally. The Company is aware of only
three previous pollucite-hosted caesium mines with Bikita in Zimbabwe and Sinclair in Western Australia now reportedly exhausted
and Tanco in Manitoba, Canada, approaching the end of its mine-life.
2
• The Company has commenced evaluating options (including a scoping metallurgical
program to test pollucite recovery using conventional X -ray ore sorting methods) to
advance and incorporate the caesium opportunity at CV13 as a potential additional saleable
product into the overall economic development of the Project – to follow completion of
the lithium-only Feasibility Study on the CV5 Pegmatite.
• The Company remains on track to deliver a maiden Ore Reserve and Feasibility Study for
lithium at the CV5 Spodumene Pegmatite in CYQ3-2025.
Darren L. Smith, Executive and Vice President of Exploration for the Company, comments: “At
Shaakichiuwaanaan, we have now defined the largest reported occurrence of pollucite in the world – by a
significant margin. To find a pollucite-hosted caesium deposit of this scale and grade is exceptionally rare,
with only three deposits globally known to have produced this extremely high-value critical and strategic
mineral.”
“The pegmatites of the Shaakichiuwaanaan Project continue to demonstrate their unique , world-class
nature for hosting abundant and varied critical minerals. With considerable Mineral Resources for lithium,
tantalum, gallium, and now caesium defined – and a Feasibility Study for lithium at CV5 on schedule for
completion this quarter – the Company is becoming increasingly well-positioned as an emerging critical
minerals powerhouse to global markets.”
Ken Brinsden, President, CEO, and Managing Director , comments: “This is another feather in the
cap of our technical team, led by Darren, with their hard work resulting in yet another world-class discovery
at Shaakichiuwaanaan. What stands out is the sheer scale and grade of this caesium discovery, relative to
anything that’s been found before globally.
It’s also a reflection of the extraordinary geology of this deposit, which hosts lithium, tantalum , and now
caesium – all high-value critical minerals – at world-class scale. Given the scale, grade , and proximity to
the CV5 Pegmatite, the new caesium discovery at Rigel and Vega has already added further substantial
value to the Shaakichiuwaanaan Project.”
“What is particularly exciting for investors is that the addressable market for caesium appears to be at a
key inflexion point, with its ability to improve the efficiency and stability of next generation terrestrial solar
technologies having the potential to drive a massive increase in global demand. Shaakichiuwaanaan stands
to play a driving role in the growth of this exciting new market. As we finalize the maiden lithium -only
Feasibility Study for the CV5 Pegmatite, we are excited to start work on unlocking the enormous potential
of the caesium resource, now outlined to NI 43 -101 and JORC standards, for our shareholders,” added
Mr. Brinsden.
PATRIOT BATTERY METALS INC. (THE “COMPANY” OR “PATRIOT”) (TSX: PMET) (ASX:
PMT) (OTCQX: PMETF) (FSE: R9GA) is pleased to announce a maiden Mineral Resource
Estimate for caesium (the “Caesium Zone MRE”) at the Rigel and Vega zones at its 100%-owned
Shaakichiuwaanaan Property (the “Property” or “Project”) located in the Eeyou Istchee James
Bay region of Quebec. The Rigel and Vega zones are hosted within the CV13 Pegmatite, which is
located ~3 km west-southwest along geological trend of the CV5 Pegmatite that is accessible year-
round by all-season road, and is situated ~13 km south of the all ‑weather Trans-Taiga Road and
powerline corridor.
3
The Company has now confirmed that the Shaakichiuwaanaan Project hosts the world’s largest
pollucite-hosted caesium pegmatite deposit (Figure 1, Figure 2, Figure 3, Table 2) after
declaring a maiden Caesium Zone MRE of:
• Rigel Caesium Zone
o Indicated: 163,000 t at 10.25% Cs2O, 1.78% Li2O, and 646 ppm Ta2O5.
• Vega Caesium Zone
o Indicated: 530,000 t at 2.61% Cs2O, 2.23% Li2O, and 172 ppm Ta2O5.
o Inferred: 1,698,000 t at 2.40% Cs2O, 1.81% Li2O, and 245 ppm Ta2O5.
The Caesium Zone MRE for Rigel and Vega , hosted within the open -pit resource component of
the CV13 Pegmatite – which forms part of the Company’s Consolidated MRE for the Project
(including both the CV5 and CV13 pegmatites) – has a total contained caesium metal content of
30.5 kt Cs2O Indicated and 40.8 kt Cs2O Inferred. The Rigel and Vega zones were interpreted
using a 0.50% Cs 2O grade constraint based on mineral processing analogues and mineralogical
analysis supporting pollucite as the predominant Cs-bearing mineral present. Coincident with the
pollucite-hosted caesium at Rigel and Vega is high-grade lithium and tantalum, present in the host
minerals spodumene and tantalite, respectively , which may be co-recovered as separate
concentrates.
The footprint of caesium mineralization at Rigel has been traced over a general area of at
least 200 m x 100 m and consists of a single, shallow dipping lens at a depth of ~50 m with a
true thickness of <2 m to ~6 m . At the Vega Zone , the footprint of the caesium
mineralization has been traced over a general area of at least 800 m x 250 m and
consists of two proximal flat-lying lenses, at a depth of ~110 m, with a true thickness of <2 m and
up to ~10 m and ~6 m, respectively (Figure 1, Figure 9, Figure 10, Figure 21) .
The Consolidated MRE 2, which includes the Rigel and Vega caesium zones, was most recently
announced on May 12, 2025 ; however, that has now been updated and restated herein this
announcement with the inclusion of caesium reporting as part of the overall consolidated
resources for the CV5 and CV13 pegmatites.
The restatement of the Consolidated MRE also includes a minor adjustment to the tonnage and
tantalum grade at the CV13 Pegmatite. The Consolidated MRE is as follows (Table 1).
• Indicated: 108.0 Mt at 1.40% Li2O, 0.11% Cs2O, 166 ppm Ta2O5, and 66 ppm Ga.
• Inferred: 33.4 Mt at 1.33% Li2O, 0.21% Cs2O, 155 ppm Ta2O5, and 65 ppm Ga.
2 The Consolidated MRE cut-off grade is variable depending on the mining method and pegmatite (0.40% Li2O open-pit, 0.60% Li2O
underground CV5, and 0.70% Li2O underground CV13). A grade constraint of 0.50% Cs2O was used to model the Rigel and Vega
caesium zones, which are entirely within the CV13 Pegmatite’s open -pit mining shape. The Effective Date of the MREs is June 20,
2025 (through drill hole CV24 -787). Mineral Resources are not Mineral or Ore Reserves as they do not have demonstrated
economic viability.
4
ABOUT CAESIUM
Mineral deposits of pollucite -hosted caesium are extremely rare globally and represent
the most fractionated component of LCT pegmatite systems, which are effectively the only primary
economic source of caesium globally. Economic deposits of caesium pegmatite are typically
on a smaller scale of <10 kt to 350 kt in size compared to deposits of lithium pegmatite that
typically range in the millions of tonnes in size (<10 Mt and rarely over 100 Mt).
Globally, it is estimated only three (3) primary caesium mines have historically operated and all
were pollucite hosted – Tanco (Canada), Bikita (Zimbabwe), and Sinclair (Australia). At Bikita and
Sinclair, the pollucite resources are reportedly to have be en exhausted in 2018 and 2019,
respectively. Tanco is understood to be approaching the end of its mine-life with extraction from
existing tailings piles and/or mine remnants being explored. At Sinclair3, the mine produced 18,629
tonnes of pollucite pegmatite ore grading 8.3% Cs2O for a contained metal content of 1,551 tonnes
Cs2O. In comparison to the size of the interpreted caesium zones at Vega (~800 m x 250 m) and
Rigel (~200 m x 100 m), the primary ore body at Sinclair was relatively small and measured ~60 m
long, up to 20 m wide, and up to 10 m thick, and was situated at a depth~40 m from surface.
The market for caesium compounds and metals is largely opaque because it is not publicly traded
like copper or gold, but rather through bi -lateral and term contracts. Further, prices vary
depending on its contained caesium form, purity and end -product use. Caesium carbonate
(Cs2CO3≥99%) currently trades at approximately US$120/kg, however in its refined form caesium
metal (Cs >99.5%), is a high value commodity comparable to gold and currently trades around
US$2,540/oz (or ~US$81 per gram4) (excluding VAT, Price Sourcing – Shanghai Metal Markets).
Caesium is currently supply constrained, with only limited sources supplying the global market. A
discovery of this size, grade, and scale has the potential to be a primary source of supply for global
markets. This includes existing applications for caesium in oil/gas drilling, medical imaging and now
new and potentially growing applications in the terrestrial solar panel industry which has the
potential to drive a significant increase in global demand . Caesium has been found to play a vital
role in significantly improving next generation solar panel efficiency, stability, and life span through
the application of perovskite crystal structures.
NEXT STEPS
With the maiden MRE for the Rigel and Vega caesium zones now completed, the Company is
actively evaluating options to advance and incorporate the caesium opportunity at CV13 as a
potential additional saleable product into the overall economic development of the Project – to
follow completion of the lithium-only Feasibility Study on the CV5 Pegmatite.
This includes completing various environmental baseline studies and additional drilling to further
convert Inferred Resources to the Indicated category and in support of future development (e.g.
geomechanical drill holes). Additionally, the Company has commenced industry engagement with
end users of caesium as well as initiated a scoping metallurgical program targeting pollucite mineral
3 Management cautions that past results or discoveries on other mineral properties or mines owned by third parties (i.e., Tanco ,
Bikita, Sinclair) may not necessarily be indicative to the presence of mineralization on the Company’s properties or the econ omic
viability of any such mineralization. There can be no assurance that future exploration efforts will result in the identifica tion of
additional mineral resources or reserves, or that the estimate of mineral resources reported within will be economically extracted
in the future.
4 Assumes conversion from troy ounce.
5
recovery using conventional X-ray ore sorting methods, which will inform a more expansive test
program that will also include subsequent recovery of spodumene (lithium) and tantalite
(tantalum). The scoping metallurgical program is using mineralized drill core collected from the
Vega Caesium Zone with subsequent testwork to expand to the Rigel Caesium Zone.
In addition, t he Company is also focused on completion of the remaining deliverables for its
lithium-focused Feasibility Study on the CV5 Pegmatite. The Feasibility Study is well advanced and
remains on schedule for completion in CYQ3-2025, with the Company recently announcing an
update on its progress on March 18, 2025.
Figure 1: Plan view footprints of the Vega and Rigel caesium zone geological models based on a
0.5% Cs2O grade constraint within the wider CV13 Pegmatite body.
6
Figure 2: Tonnage vs grade chart highlighting Rigel and Vega caesium zones as the largest pollucite-
hosted caesium p egmatite Mineral Resource in the world. Mineral Resource data sourced through July 11,
2025, from corporate disclosure. Deposit/Project data presented includes the total caesium zone resource tonnage. Mineral
Resources are presented on a 100% basis. Data is presented for all documented in-situ pollucite-hosted caesium pegmatite
deposits/projects to the knowledge of the Company. See Appendix 2 for further details and supporting information.
Figure 3: Pollucite mineralization in high-grade caesium drill intersection at ~64.5 m depth in drill
hole CV23-271 at the Rigel Zone, CV13 Pegmatite. Interval grades5 22.69% Cs2O over 1.0 m (64.0
m to 65.0 m) with XRD-Rietveld reporting a pollucite content over the interval of 58%.
5 Refer to news release dated April 9, 2025.
7
MINERAL RESOURCE STATEMENT (NI 43-101)
Table 1: Consolidated Mineral Resource Statement for the Shaakichiuwaanaan Project.
Conceptual
Mining
Constraint
Pegmatite Classification Tonnes
(t)
Li2O
(%)
Cs2O
(%)
Ta2O5
(ppm)
Ga
(ppm)
Contained
LCE
(Mt)
Open-Pit
CV5 Indicated
97,757,000 1.39 0.09 163 66 3.35
Underground 4,071,000 1.08 0.06 186 66 0.11
Total 101,828,000 1.38 0.09 164 66 3.46
Open-Pit
CV5 Inferred
5,745,000 1.16 0.09 163 61 0.17
Underground 8,153,000 1.24 0.07 136 60 0.25
Total 13,898,000 1.21 0.08 147 60 0.41
Open-Pit
CV13 Indicated
5,996,000 1.89 0.60 201 76 0.28
Underground 167,000 0.85 0.06 132 60 0.00
Total 6,163,000 1.86 0.59 199 76 0.28
Open-Pit
CV13 Inferred
18,020,000 1.44 0.32 168 70 0.64
Underground 1,462,000 1.05 0.08 75 55 0.04
Total 19,482,000 1.41 0.30 161 69 0.68
CV5 +
CV13
Indicated 107,991,000 1.40 0.11 166 66 3.75
Inferred 33,380,000 1.33 0.21 155 65 1.09
Table 2: Mineral Resources at the Rigel and Vega Caesium Zones within the CV13 Pegmatite.
Caesium
Zone Classification Tonnes
(t)
Cs2O
(%)
Li2O
(%)
Ta2O5
(ppm)
Contained
Cs2O
(t)
Rigel
Indicated 163,000 10.25 1.78 646 16,708
Inferred - - - - -
Vega
Indicated 530,000 2.61 2.23 172 13,833
Inferred 1,698,000 2.40 1.81 245 40,752
Rigel + Vega
Indicated 693,000 4.40 2.12 283 30,541
Inferred 1,698,000 2.40 1.81 245 40,752
8
• Mineral Resources were prepared in accordance with National Instrument 43 -101 – Standards for Disclosure of
Mineral Projects (“NI 43-101”) and the CIM Definition Standards (2014). Mineral Resources that are not Mineral
Reserves do not have demonstrated eco nomic 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 43-101 for this resource estimate is Todd McCracken, P.Geo., Director – Mining & Geology – Central Canada,
BBA Engineering Ltd. The Effective Date of the estimate is June 20, 2025 (through drill hole CV24-787).
• Estimation was completed using a combination of inverse distance squared (ID 2) and ordinary kriging (OK) for
CV5 and inverse distance squared (ID2) for CV13 in Leapfrog Edge software with dynamic anisotropy search
ellipse on specific domains.
• Drill hole composites at 1 m in length. Block size is 10 m x 5 m x 5 m with sub-blocking.
• Both underground and open-pit conceptual mining shapes were applied as constraints to the Consolidated MRE
Statement to demonstrate reasonable prospects for eventual economic extraction. Cut -off grades for open -pit
constrained resources are 0.40% Li 2O for both CV5 and CV13, and for underground constrained resources are
0.60% Li2O for CV5 and 0.70% Li2O for CV13. Open-pit and underground Mineral Resource constraints are based
on a long-term average spodumene concentrate price of US$1,500/tonne (6% basis FOB Bécancour) and an
exchange rate of 0.70 USD/CAD.
• Mineral Resources for the Rigel and Vega zones are hosted within the CV13 Pegmatite’s open -pit conceptual
mining shape and, therefore, are included within the Consolidated Mineral Resource Statement for CV5 and CV13
pegmatites. The Rigel and Vega zones were interpreted using a 0.50% Cs 2O grade constraint based on mineral
processing analogues and mineralogical analysis supporting pollucite as the predominant Cs -bearing mineral
present.
• Rounding may result in apparent summation differences between tonnes, grade, and contained metal content.
• Tonnage and grade measurements are in metric units.
• Conversion factors used: Li 2O = Li x 2.153; LCE (i.e., Li 2CO3) = Li2O x 2.473, Ta 2O5 = Ta x 1.221, Cs2O = Cs x
1.0602
• Densities for pegmatite blocks (both CV5 & CV13) were estimated using a linear regression function (SG = 0.0674x
(Li2O% + 0.81 x B 2O3%) + 2.6202) derived from the specific gravity (“SG”) field measurements and Li 2O grade.
Non-pegmatite blocks were assigned a fixed SG based on the field measurement median value of their respective
lithology.
SENSITIVITY ANALYSIS
The following Table 3 and Figure 4 outline the corresponding tonnage and caesium grade at various
cut-off grades for the Caesium Z one MREs, hosted within the CV13 Pegmatite and the
Consolidated MRE. In addition to evaluating sensitivities to cut-off grades, this table can help relate
the tonnage and grades at Shaakichiuwaanaan more directly to those calculated for peer deposits,
which may have applied different cut-off grades to their resources.