AUS
NZ
UK
CA
USA
IND
Critical One Energy Inc. (CSE: CRTL) has revealed encouraging preliminary metallurgical results from its flagship Howells Lake Antimony-Gold Project located in northwestern Ontario. Conducted by Blue Coast Research Ltd., the study identified that antimony is predominantly present as stibnite with high liberation rates and notably free from arsenic, mercury, and other harmful elements that typically complicate processing. This clean mineralogy enhances the company’s flexibility in choosing refinery or offtake partners as the project progresses.
Key Points
- Critical One Energy Inc. (CSE: CRTL) reported positive preliminary metallurgical outcomes from the Howells Lake Antimony-Gold Project in the Thunder Bay Mining Division, approximately 120 kilometres west of the Ring of Fire access corridor in northwestern Ontario.
- Analysis of four samples from drill hole HWL-2026-006 revealed stibnite (Sb2S3) modal abundance ranging from 10.9% to 97.1%, with liberation rates between 92.8% and 99.1%.
- The study detected no arsenic, mercury, or other deleterious minerals, offering a significant advantage for concentrate quality and processing cost efficiency.
- Upcoming phases will focus on flotation response testing, antimony recovery evaluation, and concentrate quality assessment across a wider spectrum of mineralization.
Mineralogical Analysis Confirms High-Grade Antimony Potential
The preliminary metallurgical investigation centered on four selected samples from drill hole HWL-2026-006, previously disclosed in a May 15, 2026 press release. These samples exhibited substantial stibnite content, with modal abundances spanning 10.9% to 97.1%. The samples represented diverse mineralization styles, including massive stibnite and vein- and wall-rock-hosted semi-massive stibnite, with antimony grades ranging from 1.41% to 70.7% Sb.
In addition to stibnite, the study identified berthierite (FeSb2S4) in three samples at modal abundances between 0.8% and 7.9%, along with trace amounts of chalcostibite (CuSbS2). These secondary antimony minerals contribute to the overall antimony inventory, indicating a mineralized system with diverse antimony-hosting phases that may offer processing flexibility.
Outstanding Mineral Liberation Supports Flotation Concentration
A key highlight of the study is the high liberation rates of principal antimony minerals after grinding to 106 micrometres. Stibnite liberation ranged from 92.8% to 99.1%, while berthierite liberation was between 84.9% and 89.7%. These results suggest that antimony minerals separate efficiently from surrounding phases during comminution, facilitating effective flotation concentration.
Liberation data were obtained using TIMA14 (Tescan Integrated Mineral Analyzer), an SEM-based automated mineralogy tool that identifies minerals and their associations. High liberation rates imply that future flotation testing may achieve efficient separation without requiring excessive fine grinding, potentially reducing capital and operating costs for processing.
Absence of Arsenic and Mercury Lowers Processing Challenges
The study notably found no arsenic, mercury, or other deleterious minerals in the four samples tested. This compositional purity is significant, as many global antimony deposits contain arsenic and mercury that complicate processing, increase environmental costs, and reduce concentrate marketability. Duane Parnham, Founder, Executive Chairman, and CEO of Critical One, emphasized that this clean mineralogy expands options for refinery and offtake partnerships.
The lack of these problematic elements may reduce technical and regulatory barriers in concentrate production and marketing, enhancing the project’s attractiveness to concentrate buyers and processors. Many antimony processors enforce strict arsenic and mercury limits due to health and environmental concerns. The Howells Lake mineralogy could command premium pricing or lower processing premiums compared to typical antimony concentrates with higher deleterious content.
Preliminary Flotation Potential and Upcoming Metallurgical Testing
Based on mineralogy and liberation results, the study suggests that antimony minerals may be amenable to flotation concentration, a cost-effective and industry-standard method for stibnite. Although formal flotation tests have not yet been conducted, the high liberation of stibnite and berthierite supports this potential.
The company plans further metallurgical testing to evaluate flotation response, antimony recovery, concentrate quality, and variability across a broader range of Howells Lake mineralization. These tests will guide processing flowsheet development as the project advances from mineral identification to engineering-level process assessment.
Strategic Role in Critical One's Critical Minerals Portfolio
Howells Lake is Critical One Energy’s flagship antimony-gold project, providing direct exposure to antimony, a critical metal of growing strategic importance in Western nations. Antimony is vital for defence, aerospace, electronics, and energy applications, with supply constraints elevating its priority. Canada’s stable permitting environment and technical capacity make it an attractive jurisdiction for antimony development aligned with Western supply chain security.
Alongside Howells Lake, Critical One holds uranium and copper assets in Namibia, diversifying its critical minerals and energy metals portfolio. The company’s experienced management team is well-positioned to advance high-value projects amid rising demand for secure critical minerals supply.
Qualified Person Review and Regulatory Compliance
The technical information in this announcement has been reviewed and approved by Matthew Trenkler, P. Geo., Chief Geological Officer of Critical One Energy Inc. Trenkler qualifies as a "Qualified Person" under National Instrument 43-101 Standards of Disclosure for Mineral Projects, ensuring the technical content meets Canadian regulatory standards.
Qualified Person oversight is a standard requirement for Canadian-listed mining companies, providing assurance that mineral project disclosures are accurate and based on sound geological and technical evaluation. This certification confirms compliance with Canadian securities regulations.
Impact on Project Advancement and Investor Outlook
The positive metallurgical findings mark a significant de-risking milestone for the Howells Lake Project. Previous drilling and testwork have confirmed high-grade antimony mineralization, and the current data demonstrate favorable processing characteristics that support economic extraction and concentration.
Investors will likely monitor forthcoming updates on flotation testwork, additional drilling results, and project development timelines. The strong preliminary metallurgical data may positively influence investor sentiment regarding project viability and the company’s ability to secure strategic partners or financing.
Antimony Market Dynamics and Critical Minerals Supply Chain
This announcement comes amid heightened geopolitical focus on securing Western supply chains for critical minerals and energy metals. Antimony’s role in defence and aerospace—used in electronics, flame retardants, and advanced materials—makes it strategically important. Global supply constraints and China’s dominance in production have triggered initiatives to diversify and strengthen Western antimony sources.
Successful development of projects like Howells Lake could reduce Western reliance on imports and support national security objectives related to critical minerals. This strategic backdrop enhances the project’s appeal to financiers, offtake partners, and government stakeholders involved in critical minerals policy.
