High-Grade Pollucite Confirmed as Main Caesium Host Mineral at the Vega and Rigel Zones
Press Release
June 10, 2025
Identification of other potential high-value by-products within the existing lithium Mineral Resource shows the highly evolved pegmatites at Shaakichiuwaanaan as a potential major host for further critical metals.
Highlights
- Pollucite confirmed as the principal mineral host for the caesium discovered recently at both the Vega and Rigel zones at the CV13 Pegmatite:
- Pollucite is considered the optimal mineral host for caesium in Li-Cs-Ta (“LCT”) pegmatites due to its high caesium content (typically >30%) and its relative ease of processing and recovery.
- Up to 75% pollucite in individual core sample (1.1 m at 26.6% Cs2O[1]).
- Caesium within the Vega and Rigel zones will be included in the next Mineral Resource update for the Project, targeted for Q3-2025. Interpreted sizes of the Vega and Rigel zones are significant – footprints of ~800 m x 250 m (Vega) and ~200 m x 100 m (Rigel).
- The Company has commenced evaluating options to advance and incorporate the caesium opportunity at CV13 as a potential by-product into the overall economic development of the Project, to follow completion of the lithium-only Feasibility Study on the CV5 Pegmatite.
- Caesium pricing varies based on its end-product form and purity; however, in its refined form, caesium metal (Cs >99.5%) is a high value commodity similar to gold and currently trades around US$2,540/oz (excluding VAT, Source – Shanghai Metal Markets).
- Shaakichiuwaanaan LCT pegmatites are highly evolved through the process of crystal fractionation during formation, resulting in extreme enrichment of lithium, caesium, and tantalum – each at potentially world-class scale.
- Tantalum and gallium are already part of the existing Mineral Resource with potential to become meaningful future by-products.
- The lithium-only Feasibility Study based on the CV5 Mineral Resource component remains on-track for completion in Q3-2025, with the economic potential of the critical metal by-products to be assessed thereafter.
Ken Brinsden, President, CEO, and Managing Director, comments: “The confirmation of widespread pollucite mineralization – the optimal host mineral for caesium – at the Vega and Rigel zones marks another important step forward in evaluating the economic potential of this exciting discovery. As we advance towards a preliminary mineral processing program to evaluate recovery of caesium, the team is working on a maiden MRE for caesium that is anticipated to be announced before the end of third-quarter 2025.
“The presence of significant caesium mineralization at Shaakichiuwaanaan, in addition to lithium and tantalum, reinforces the amazing endowment of the geology and the potential for other critical and strategic metals to further enhance and diversify future Project economics. We are very keen to explore these value-add opportunities on top of what is already recognized as a world-class lithium pegmatite in its own right,” added Mr. Brinsden.
Patriot Battery Metals Inc. (the “Company” or “Patriot”) (TSX: PMET) (ASX: PMT) (OTCQX: PMETF) (FSE: R9GA) is pleased to provide an update on caesium – a high-value critical and strategic metal – identified at the CV13 spodumene pegmatite, at its 100%-owned Shaakichiuwaanaan Property (the “Property” or “Project”) located in the Eeyou Istchee James Bay region of Quebec. The CV13 Spodumene Pegmatite is located approximately 3 km west-southwest along geological trend of the CV5 Spodumene Pegmatite, which is situated approximately 13 km south of the regional and all‑weather Trans-Taiga Road and powerline infrastructure corridor, and is accessible year-round by all-season road.
The Shaakichiuwaanaan Li-Cs-Ta (“LCT”) pegmatites are highly evolved through the process of crystal fractionation during formation, whereby mineral crystallization leads to progressive changes in the chemistry of the remaining melt, resulting in increasingly rare minerals being formed as the process unfolds. This process of pegmatite formation most commonly leads to only modest enrichment of lithium and other critical metals. However, in the LCT pegmatites at Shaakichiuwaanaan this process has resulted in the extreme enrichment of lithium, caesium, and tantalum – each at potentially world-class scale – as well as other potentially recoverable critical and strategic metals (e.g., gallium).
Each of these critical metals could become further value-added by-products to the envisioned lithium operation at Shaakichiuwaanaan. Additional information is provided below describing the caesium opportunity and the steps being taken to evaluate development of this unique asset. Further details will be provided on the other potential by-products identified, including tantalum and gallium, in the coming weeks.
Caesium Opportunity
In news releases dated March 2 and April 9, 2025, the Company announced the discovery of significant caesium mineralization in drill hole at the CV13 Pegmatite within the Vega and Rigel zones. Initial drill results include:
- 1 m at 4.87% Cs2O, including 7.1 m at 7.39% Cs2O (Vega, CV24-520), and
- 0 m at 13.32% Cs2O, including 2.0 m at 22.90% Cs2O (Rigel, CV23-255).
The Company is pleased to report that XRD-Rietveld mineralogical analysis completed on drill core samples from the Vega and Rigel caesium zones has confirmed pollucite as the dominant caesium-bearing mineral present (Figure 1). A pollucite content high of 74.2% was reported over 1.1 m in drill hole CV23-204, assaying 26.6% Cs2O.
Pollucite is considered the optimal mineral host to caesium in LCT pegmatites due to its very high caesium content (typically >30%) and its relative ease of processing and recovery. Pollucite is typically recovered using standard and conventional ore sorting methods as well as potential secondary flotation. The Company has completed collection of drill core samples from the Vega Zone for an ore sorting test program that will evaluate pollucite (caesium) concentrate recovery ahead of the typical spodumene (lithium) and tantalite (tantalum) recovery circuits.
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