Beyond Gold: RZOLV’s Potential Role in Critical Minerals Recovery

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RZOLV’s potential role in cleaner critical-minerals recovery from secondary streams, residues, and complex concentrates

Reza Kafaei, Hanif Jafari, Duane Nelson: - RZOLV Technologies

May 5^th, 2026 – 15 pages

Abstract

RZOLV Technologies is best known for its non-cyanide precious-metals recovery platform, but recent screening results suggest that the chemistry may have broader relevance across selected critical minerals, rare earth elements, heavy rare earths, technology metals, concentrates, residues, tailings, and recycled feedstocks. This article examines RZOLV’s potential role as a controlled hydrometallurgical screening and recovery platform for materials where conventional processing may leave valuable metals behind or require complex downstream treatment.

Previous unoptimized RZOLV screening has shown measurable dissolution of several rare earth and critical elements, including cerium, lanthanum, neodymium, gadolinium, dysprosium, erbium, thulium, yttrium, cobalt, vanadium, tellurium, and indium. These results do not prove universal applicability, but they support further evaluation of RZOLV on project-specific concentrates, middlings, tailings, process residues, by-product streams, and recycled materials. The most important test will not be dissolution alone, but whether target metals can be recovered selectively while controlling impurities, reagent consumption, residue leachability, water chemistry, and environmental performance.

The article positions RZOLV not as a replacement for established rare earth or critical-mineral processing flowsheets, but as a potential supplemental module for selective dissolution, by-product recovery, heavy rare earth deportment testing, process-stream polishing, tailings scavenging, environmental residue treatment, and circular-economy metal recovery. If validated through representative bench and pilot testing, RZOLV could help recover more value from materials already being mined, processed, discarded, or recycled, while supporting cleaner and more localized critical-minerals supply chains.

Executive Summary

The global race for critical minerals is no longer just about finding new deposits. It is increasingly about developing cleaner, more selective, and more locally controllable ways to recover value from the materials already being mined, concentrated, discarded, or recycled.

Rare earths, heavy rare earths, cobalt, vanadium, tellurium, indium, silver, and other strategic metals are central to defense, clean energy, electronics, advanced manufacturing, permanent magnets, photovoltaics, and industrial independence. But the processing pathways for many of these materials remain complex, capital-intensive, environmentally sensitive, and often dependent on offshore refining or smelting capacity.

Originally developed and advanced around non-cyanide precious-metals recovery, RZOLV is increasingly being evaluated as more than a gold-leach chemistry. The platform may have potential as a controlled hydrometallurgical screening tool for selected critical minerals, rare earths, heavy rare earths, technology metals, process residues, tailings, concentrates, and recycled material streams.

A platform, not just a reagent

RZOLV is best understood as a controlled, water-based hydrometallurgical platform. Its core value lies in managing chemistry within a defined pH–ORP window, where dissolution, complexation, reagent stability, impurity behavior, and downstream recovery can be evaluated in a disciplined way.

That distinction is important. Critical-minerals processing is rarely straightforward. Many strategic metals are hosted in complex mineral matrices, associated with problematic impurities, or distributed across multiple process streams. A useful hydrometallurgical tool does not necessarily need to replace an entire primary flowsheet. It may create value by improving one part of the circuit: recovering residual metals from tailings, upgrading a concentrate fraction, scavenging by-products, polishing process streams, or improving residue stability.

This is the more realistic and potentially more valuable role for RZOLV in critical minerals: not as a universal replacement for conventional processing, but as a supplemental recovery and process-optimization platform.

Early screening results point beyond gold

RZOLV’s potential relevance to critical minerals is supported by previous internal screening results showing measurable dissolution of a broad suite of rare earth, heavy rare earth, and technology metals.

Reported unoptimized RZOLV dissolution results included:

Element	Reported 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%

These results are significant because they show RZOLV is not limited to gold and silver chemistry. The response profile includes light rare earth elements such as cerium, lanthanum, and neodymium, as well as heavy rare earth-associated elements such as dysprosium, erbium, thulium, gadolinium, and yttrium.

It also includes cobalt, vanadium, tellurium, and indium — metals with strategic relevance to energy storage, specialty alloys, electronics, solar technologies, and advanced industrial applications.

The results do not prove universal applicability. Mineralogy, liberation, host phases, impurities, pH, ORP, reagent dose, temperature, residence time, and downstream recovery method will all determine whether RZOLV is relevant to any specific feedstock. But they do provide a strong reason to evaluate the platform more broadly.

Heavy rare earths: a strategic test case

Heavy rare earths are among the most strategically important materials in the critical-minerals universe. Elements such as dysprosium, terbium, yttrium, erbium, thulium, gadolinium, holmium, ytterbium, and lutetium are used in permanent magnets, lasers, phosphors, defense systems, specialty alloys, electronics, and advanced manufacturing.

They are also among the most supply-sensitive materials, because production and separation capacity remain geographically concentrated.

For RZOLV, the important question is not simply whether it can dissolve rare earths in general. The more important question is whether the chemistry can create a useful deportment or selectivity effect.

Recovering value from overlooked streams

The critical-minerals industry is full of value that does not always report cleanly to the main product. Strategic metals can be distributed across middlings, cleaner rejects, low-grade concentrates, acid-leach residues, magnetic separation residues, gravity separation residues, process liquors, and tailings.

In many cases, the primary flowsheet is designed to optimize one product, while secondary metals are left behind, diluted, or treated as impurities.

That creates an opening for a supplemental hydrometallurgical technology.

RZOLV could be evaluated on several potential streams:

Material Stream	Potential RZOLV Role
Primary concentrates	Selective dissolution or upgrading of target metals
Heavy rare earth-rich fractions	Evaluate HREE deportment and selectivity
Middlings / cleaner rejects	Recover residual value from off-spec material
Tailings	Scavenge remaining rare earth or critical-metal values
Magnetic / gravity separation residues	Test residual recoverability after physical beneficiation
Acid-leach residues	Recover value left after conventional acid processing
By-product-rich streams	Evaluate Co, V, Te, In, Zr, Nb, Ta, Hf, Ti, or other associated metals
Process liquors / wash streams	Polishing, selective recovery, or solution conditioning
Environmental residues	Reduce residual metal inventory or improve leachability

This is where RZOLV could become particularly useful. It may not need to be the primary process. It may become the tool used to recover additional value from streams that would otherwise be underutilized.

The circular economy opportunity

Critical-minerals recovery is not limited to mining. It increasingly includes recycled materials, solar panel concentrates, electronics residues, industrial by-products, battery-related streams, and other secondary feedstocks.

This is an important part of the RZOLV story because the platform has already shown promising behavior on recycled and secondary materials. In earlier photovoltaic concentrate testing, RZOLV achieved strong silver dissolution from a high-grade PV-derived concentrate under ambient, agitated conditions.

That matters because the solar recycling sector is still developing downstream value-capture solutions. Many recyclers can recover glass, aluminum frames, and bulk materials, but the higher-value metals — including silver, copper, tellurium, indium, gallium, and other specialty metals depending on feed type — often require more sophisticated downstream hydrometallurgy.

A modular, water-based process that can recover value from concentrates or residues could help shift recycling economics from bulk material handling toward higher-value metal recovery.

In that sense, RZOLV may have potential not only in mining, but in the broader circular economy for precious and critical metals.

Environmental positioning matters

Critical-minerals projects often face a difficult paradox. The materials are essential for clean energy, electrification, advanced manufacturing, and national security — but their extraction and processing can raise environmental and community concerns.

Any new hydrometallurgical technology must therefore be judged not only by what it dissolves, but by how it manages water, residues, toxicity, impurities, and closure.

RZOLV’s environmental positioning may be relevant here. Independent ecotoxicity testing reported by RZOLV indicated a substantially lower acute trout toxicity profile than a cited cyanide reference value under the reported test conditions. The company has also appropriately cautioned that such comparisons are contextual and not a substitute for site-specific environmental testing.

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

However, a lower-toxicity, non-cyanide processing narrative may be valuable in critical-minerals settings where permitting credibility, stakeholder trust, water management, and residue stability are central to project acceptance.

The recovery challenge

Dissolving metals is only half the battle. The real commercial test is whether the dissolved metals can be recovered economically and selectively.

For critical minerals, that means RZOLV-generated solutions would need to be evaluated against established or testable recovery methods, including:

Recovery Method	Potential Role
pH-staged precipitation	Bulk metal or rare earth recovery
Oxalate precipitation	Conventional rare earth recovery pathway
Ion exchange	Selective capture of REEs or impurities
Chelating resins	Scavenging from dilute or complex streams
Solvent extraction screening	Separation and purification potential
Membrane or polishing technologies	Liquor cleanup and water management
Electrochemical conditioning	ORP control, solution recycle, or impurity management

The key metric is not only percent dissolution. It is selectivity. A successful critical-minerals application would need to show that the target metals dissolve at useful levels while impurity dissolution remains manageable. Iron, aluminum, calcium, magnesium, phosphorus, fluorine, uranium, thorium, and other elements may all influence whether a solution is commercially recoverable.

Strategic value: unlocking more from the same tonne

The future of critical minerals will not be defined only by new mines. It will also be defined by better recovery from every tonne already mined and processed.

If validated on specific feedstocks, RZOLV could support:

Strategic Objective	Potential RZOLV Contribution
Higher resource utilization	Recover metals from middlings, tailings, and residues
By-product monetization	Capture associated critical or technology metals
Heavy rare earth optimization	Test HREE deportment and enrichment pathways
Environmental improvement	Reduce residual metal inventory or improve residue behavior
Local value capture	Support domestic or regional hydrometallurgical processing
Circular economy recovery	Treat PV, e-waste, and industrial concentrates
Lower-toxicity optionality	Provide a non-cyanide processing route for selected streams

The strongest case is not that RZOLV will replace established critical-mineral flowsheets overnight. It is that RZOLV may add an additional hydrometallurgical tool where projects need more recovery, better residue outcomes, or more localized processing optionality.

A careful but compelling opportunity

The critical-minerals sector does not need more unsupported technology claims. It needs practical tools that can be tested, measured, integrated, and validated.

RZOLV’s early critical-minerals screening results justify that next step. The chemistry has shown measurable dissolution across a suite of rare earths, heavy rare earths, and technology metals. The platform is controllable. The environmental positioning is potentially favorable. The application windows are real.

The bottom line

RZOLV may have started as a non-cyanide gold recovery technology, but its broader potential may lie in the controlled recovery of valuable metals from complex and underutilized streams.

Its early critical-minerals results suggest possible relevance to rare earths, heavy rare earths, cobalt, vanadium, tellurium, indium, and other strategic materials. Its platform design may allow it to be tested on concentrates, middlings, tailings, residues, process liquors, and recycled materials. Its lower-toxicity narrative may support cleaner processing discussions in sensitive jurisdictions and circular economy applications.

If validated through representative testwork, RZOLV could become part of a larger shift in mineral processing: from single-metal extraction toward smarter, cleaner, multi-metal value recovery.

In the critical-minerals era, the winning technologies may not be those that simply mine more. They may be the ones that recover more value from what the world 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.