RZOLV Looks Beyond Gold as Critical Minerals Testing Opens New Front

Controlled hydrometallurgical platform could complement precious-metals recovery with applications in rare earths, technology metals, residues and recycled feedstocks

RZOLV Technologies is best known for its non-cyanide precious-metals recovery platform, but the company’s latest critical-minerals work suggests the technology may have a broader role to play in the next phase of hydrometallurgical processing.

The opportunity is not simply to find more ore. Across the critical-minerals sector, a growing challenge is how to recover more value from material that is already being mined, concentrated, rejected, stockpiled or recycled. Rare earths, heavy rare earths, cobalt, vanadium, tellurium, indium, silver and other strategic metals are increasingly central to defence, clean energy, electronics, permanent magnets, photovoltaics and advanced manufacturing — yet many remain difficult to process economically and cleanly.

RZOLV’s latest paper positions the technology as a controlled hydrometallurgical screening and recovery platform for selected critical-mineral-bearing streams. The company is careful not to frame the chemistry as a replacement for established rare earth or critical-mineral flowsheets. Instead, the opportunity is more targeted: selective dissolution, by-product recovery, heavy rare earth deportment testing, process-stream polishing, tailings scavenging, environmental residue treatment and circular-economy metal recovery.

From gold reagent to hydrometallurgical platform

The critical-minerals work is best understood as a complement to RZOLV’s core precious-metals business, not a departure from it.

RZOLV was developed around non-cyanide gold and silver extraction, but its broader technical thesis is based on controlled pH–ORP chemistry. In practical terms, the system is designed to manage dissolution, complexation, reagent stability, impurity behaviour and downstream recovery inside a defined operating window. That platform approach may allow the chemistry to be screened across multiple material types rather than limited to a single-metal application.

For the critical-minerals sector, that distinction matters. Many strategic metals do not report cleanly to a single product stream. They can be distributed across middlings, cleaner rejects, low-grade concentrates, acid-leach residues, magnetic or gravity separation residues, process liquors and tailings. In those cases, the value of a supplemental hydrometallurgical tool may lie in improving one part of the circuit rather than replacing the primary flowsheet.

Early screening points to broader metal response

The most striking part of the paper is the early unoptimized screening data. RZOLV reported measurable dissolution across a suite of rare earth, heavy rare earth and technology metals, including cerium, cobalt, gadolinium, yttrium, neodymium, dysprosium, lanthanum, erbium, vanadium, thulium, tellurium and indium.

Element	RZOLV dissolution / recovery
Cerium	73.50%
Cobalt	60.00%
Gadolinium	45.00%
Yttrium	43.55%
Neodymium	43.48%
Dysprosium	42.81%
Lanthanum	40.74%
Erbium	38.10%
Vanadium	33.33%
Thulium	31.43%
Tellurium	27.34%
Indium	23.53%

The data are preliminary and feed-specific. They do not establish commercial recovery, nor do they prove applicability to any specific deposit, concentrate, residue or recycled material stream. But they are enough to justify broader testwork, particularly where conventional processing leaves value behind or where downstream recovery remains complex.

The inclusion of heavy rare earth-associated elements such as dysprosium, erbium, thulium, gadolinium and yttrium is especially notable. Heavy rare earths remain among the most strategically sensitive critical minerals because of their use in magnets, lasers, phosphors, defence technologies, electronics and specialty materials.

The real test is selectivity

In critical-minerals processing, dissolving metal is only the first step. The more important question is whether the target metals can be recovered selectively and economically from solution.

RZOLV’s critical-minerals paper makes that point clearly. A successful application would need to show useful dissolution of target metals while keeping impurity dissolution manageable. Iron, aluminum, calcium, magnesium, phosphorus, fluorine, uranium, thorium and other elements can all determine whether a pregnant solution is commercially recoverable.

The likely recovery pathway would depend on the feed and the chemistry of the resulting solution. Potential options include pH-staged precipitation, oxalate precipitation, ion exchange, chelating resins, solvent extraction screening, membrane or polishing technologies and electrochemical conditioning.

That makes the next phase of work more than a leach test. It requires a full hydrometallurgical evaluation: mineralogy, head assays, rare earth distribution, impurity deportment, pH–ORP response, reagent consumption, residue leachability, downstream recovery and solution recycle.

Recovering more from overlooked streams

The strongest near-term application may be secondary and intermediate streams.

The paper identifies several potential material types where RZOLV could be evaluated: primary concentrates, heavy rare earth-rich fractions, middlings, cleaner rejects, tailings, magnetic or gravity separation residues, acid-leach residues, by-product-rich streams, process liquors, wash streams and environmental residues.

That list reflects a practical reality in critical-minerals development. A primary flowsheet may be optimized for one product, while other valuable metals report to waste, low-grade fractions or impurity streams. If RZOLV can recover even a portion of that residual value — or improve residue stability — it could become a useful process-optimization tool.

Potential applications include recovering residual metals from tailings, upgrading concentrate fractions, scavenging by-products, reducing residual metal inventory, improving leachability profiles and supporting more local or domestic value capture.

A circular-economy angle

RZOLV’s critical-minerals opportunity is not limited to mined feedstocks.

The paper also points to recycled and secondary materials, including solar panel concentrates, electronics residues, industrial by-products and other circular-economy streams. In earlier photovoltaic concentrate testing, RZOLV showed strong silver dissolution from a high-grade PV-derived concentrate under ambient, agitated conditions.

That is strategically relevant because many recyclers can recover bulk materials such as glass, aluminum frames and external wiring, while higher-value metals often require more advanced downstream hydrometallurgy. A modular, water-based process that can treat concentrated residues could help shift recycling economics from bulk handling toward metal value recovery.

Environmental profile remains part of the pitch

Critical-minerals projects increasingly face a paradox. They are essential to electrification, clean energy and industrial security, but processing can raise concerns around reagents, water, residues, toxicity, impurities and closure.

RZOLV’s non-cyanide profile may help in that discussion, but the company’s positioning remains appropriately qualified. The paper notes that independent ecotoxicity testing reported by RZOLV indicated a substantially lower acute trout toxicity profile than a cited cyanide reference value under the reported conditions. It also notes that such comparisons are contextual and not a substitute for site-specific environmental testing.

That qualification is important. RZOLV is not being presented as risk-free. Any critical-minerals application would still require detailed testing of solution chemistry, residue leachability, metals mobility, reagent consumption, water treatment, toxicity and full mass balance.

A disciplined expansion strategy

For RZOLV, the critical-minerals work broadens the company’s technical narrative. It supports the idea that RZOLV may be more than a single-purpose gold reagent. The platform could become a screening and recovery tool for complex, multi-metal streams where conventional processing leaves value behind.

But the commercial message needs to remain disciplined. The current data do not establish commercial recovery. They do not replace project-specific metallurgical work. They do not prove that RZOLV can recover rare earths or technology metals from every feed. They do, however, provide a credible basis for structured testing.

The next step is to determine whether the chemistry can create real process value: selective dissolution, recoverable pregnant solutions, manageable impurities, acceptable reagent consumption, stable recycle behaviour and improved residue profiles.

The bottom line

RZOLV’s critical-minerals work is not a pivot away from precious metals. It is a logical extension of the same controlled hydrometallurgical platform.

The company’s core technology remains rooted in non-cyanide precious-metals recovery. But early screening results suggest the same chemistry may have relevance to selected rare earths, heavy rare earths, technology metals, residues, tailings, concentrates and recycled feedstocks.

If validated through representative bench and pilot testing, RZOLV could become part of a broader shift in mineral processing — from single-metal extraction toward smarter, cleaner, multi-metal recovery.

In the critical-minerals era, the winning technologies may not only be those that mine more. They may be the ones that recover more value from what the industry is already moving, processing and discarding.

Disclaimer

This article is provided for general information and discussion purposes only and does not constitute a technical report, feasibility study, preliminary economic assessment, mineral resource or reserve estimate, engineering study, environmental assessment, investment advice, or a recommendation to buy or sell securities.

Statements regarding the potential application of RZOLV to critical minerals, rare earth elements, heavy rare earths, technology metals, advanced materials, residues, concentrates, tailings or recycled feedstocks are preliminary and forward-looking. Actual results may differ materially and remain subject to representative testwork, independent verification, metallurgical validation, downstream recovery testing, environmental assessment, regulatory review and economic analysis.

Previous RZOLV screening results should not be interpreted as evidence of commercial recovery or applicability to any specific project or material stream. No assurance can be given that RZOLV will achieve commercial recovery, selectivity, environmental benefits, regulatory approval or economic viability in any critical-minerals application.

Neither the TSX Venture Exchange nor its Regulation Services Provider accepts responsibility for the adequacy or accuracy of this article.