Post: How RZOLV May enable Safe, Predictable Gold Extraction in Cyanide-Banned Regions

By Duane Nelson, President & CEO, RZOLV Technologies Inc - December 4th, 2025

Around the world, dozens of mining jurisdictions now enforce partial or complete restrictions on sodium cyanide. These policies—whether national laws, provincial bans, protected watershed regulations, or permit-level constraints—create a structural challenge for gold operators because the only proven large-scale leach reagent is often not legal or socially acceptable to use. Historically, no alternative chemistry has combined performance, reliability, safety, and operational compatibility well enough to function as a true replacement. Most previous attempts failed at scale due to high cost, inconsistent leaching kinetics, environmental instability, or incompatibility with standard CIP/CIL circuits. RZOLV fundamentally changes this landscape.

In cyanide-restricted regions, operators have traditionally faced an unworkable choice: rely on smelter-dependent processing with limited economics, attempt to install costly, high-security cyanide systems in the hope regulators will approve them, or abandon otherwise viable gold resources entirely. RZOLV removes this barrier by offering a non-toxic, water-based leaching system capable of delivering predictable recoveries to solution, strong loadings onto activated carbon, clean electrowinning and dore production, and stable metallurgical behavior across variable mineralogies. These attributes allow projects to advance in jurisdictions where cyanide cannot be deployed at any scale.

Regulators tend to accept low-hazard reagents more readily because cyanide oversight typically involves acute toxicity controls, multi-stage detoxification requirements, strict transportation and storage protocols, and intensive water and wildlife monitoring. By contrast, RZOLV does not require cyanide detoxification, carries a dramatically lower hazard classification, and simplifies both transport and on-site handling. These characteristics materially improve the likelihood of obtaining a processing permit and reduce the regulatory burden associated with mining operations.

A central challenge in cyanide-banned jurisdictions is that alternative chemistries often behave unpredictably when ore conditions change. RZOLV was engineered specifically to tolerate mineralogical variability, including fluctuating pH drift, high sulfide content, iron-rich gangue reactions, and diverse oxide–sulfide domains. Across hundreds of lab trials and ongoing 100-tonne commercial testing, the reagent has demonstrated repeatable dissolution profiles, allowing accurate leach modeling and reliable forecasting of extraction yields. It also shows strong affinity for activated carbon with minimal competitive adsorption, fast loading rates, and stable elution behavior—essentials for operators relying on existing CIP/CIL infrastructure. Furthermore, RZOLV-loaded carbon strips cleanly in standard AARL or Zadra circuits, producing eluates suitable for predictable electrowinning, low impurity deposition, and conventional dore bar production. Together, these characteristics allow mines to integrate RZOLV into standard gold-recovery flowsheets without requiring new downstream equipment.

The implications are significant. Cyanide bans have historically sterilized vast quantities of gold resources—Alpine and EU deposits restricted by national policy, South American projects located within protected watersheds, U.S. districts governed by county-level prohibitions, and numerous Asian and African regions where environmental codes have tightened. RZOLV reactivates these resources by enabling heap and vat leach projects previously blocked by cyanide policy, allowing CIP/CIL operations in provinces where cyanide cannot be transported, and making the processing of low-grade or complex materials economically viable. This opens an entirely new development pipeline for mining companies and offers governments a path to unlock dormant economic value without increasing environmental risk.

By enabling effective leaching, predictable carbon loading, clean stripping, and dore' production—all without cyanide—RZOLV provides a fundamentally new framework for permitting and mine development. Projects can proceed in regions where cyanide is banned, explorers can convert stranded deposits into economic assets, operators can avoid costly detox plants and high-hazard infrastructure, and regulators can approve gold projects with meaningfully reduced risk profiles. This alignment of technical performance and regulatory acceptability is precisely what the gold sector has lacked.

RZOLV does not simply offer a cost-effective alternative to cyanide—it makes gold mining possible in places where cyanide is not, and cannot be, an option.

APA Reference List

Cyanide Regulations and Jurisdictional Bans

Czech Republic. (1988). Act No. 44/1988 Coll. – Mining Act. Government of the Czech Republic.European Parliament. (2006). Directive 2006/21/EC on the management of waste from extractive industries. Official Journal of the European Union.Germany. (1980). Federal Mining Act (BBergG). Government of Germany.Hungary. (1993). Act XLVIII of 1993 on Mining. Government of Hungary.Province of Chubut. (2003). Law 5001 – Prohibition of cyanide in mining. Government of Argentina.Province of Mendoza. (2007). Law 7722 – Restrictions on chemical reagents in mining. Government of Argentina.Province of Córdoba. (2008). Law 9526 – Ban on cyanide and mercury. Government of Argentina.Costa Rica. (2010). Executive Decree 34801-MINAET – National open-pit and cyanide ban. Ministry of Environment.State of Montana. (1998). Initiative 137 – Prohibition of cyanide heap leaching. Montana Secretary of State.

Environmental Toxicology and Risk Assessments

International Cyanide Management Institute. (2017). International Cyanide Management Code for the manufacture, transport, and use of cyanide in the production of gold.United Nations Environment Programme. (2010). Cyanide spill risk assessment and management guidelines. UNEP Chemicals Branch.U.S. Environmental Protection Agency. (2023). Cyanide hazard summary (IRIS Toxicological Profile). U.S. EPA.World Health Organization. (1992). Environmental health criteria 65: Cyanides. WHO Press.

Alternative Lixiviants and Hydrometallurgy

Abbruzzese, C., Fornari, P., Massidda, R., Veglio, F., & Ubaldini, S. (1995). Thiosulphate leaching for gold hydrometallurgy. Minerals Engineering, 8(7), 679–690.Aylmore, M. G. (2005). Alternative lixiviants to cyanide for leaching gold ores. In M. Adams (Ed.), Gold ore processing: Project development and operations (pp. 501–539). Elsevier.La Brooy, S. R., Linge, H. G., & Walker, G. S. (1987). Review of gold extraction from ores. Minerals Engineering, 1(2), 121–139.Marsden, J., & House, C. (2006). The chemistry of gold extraction (2nd ed.). SME Publishing.Parga, J. R., & Valenzuela, J. L. (2008). Alternative gold recovery using thiosulfate leaching from carbonaceous ore. Hydrometallurgy, 94(1–4), 29–35.SGS Minerals Services. (2008–2023). Technical bulletins on gold leaching, CIP/CIL, and alternative lixiviants. SGS.

Carbon Adsorption, Elution, and Electrowinning

Anglo American Research Laboratories. (1989). AARL elution procedure manual. Johannesburg, South Africa.Habashi, F. (1999). Hydrometallurgy: Principles and applications. Metallurgie Extractive Quebec.Zadra, J. B. (1950). A process for the recovery of gold from activated carbon by leaching and electrolysis. U.S. Bureau of Mines Report of Investigations, 4672.Dow Chemical Company. (2020). Activated carbon for gold recovery: Technical data sheets. Dow Global Filtration.

Pilot Testing, Leach Kinetics, and Scaling Standards

ASTM International. (2017). ASTM D5715 – Standard test method for determining gold in leach solutions. ASTM International.ASTM International. (2019). ASTM D6317 – Standard practice for analysis of leaching kinetics in metallurgical systems. ASTM International.International Council on Mining and Metals. (2021). Guidance on pilot testing and validation of new hydrometallurgical technologies. ICMM.Society for Mining, Metallurgy & Exploration. (2020). Scale-up methodologies for mineral processing and hydrometallurgy. SME Technical Guidance Document.

Water, Tailings, and Effluent Compliance

Canadian Ministry of Environment. (2021). Metal and Diamond Mining Effluent Regulations (MDMER). Government of Canada.Global Industry Standard on Tailings Management. (2020). Principles and requirements for chemical hazard minimization in tailings. ICMM, UNEP & PRI.European Parliament. (2000). Directive 2000/60/EC establishing a framework for Community action in the field of water policy (Water Framework Directive). Official Journal of the European Communities.

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Disclosure and Cautionary Statement

This article has been published by RZOLV Technologies Inc. as part of its corporate communications and investor relations activities and reflects the views and opinions of management as of the date of publication. It is provided for general informational purposes only and does not constitute investment advice, an offer to sell, or a solicitation to buy securities. Certain statements in this article may constitute forward-looking information within the meaning of applicable Canadian securities laws and are subject to risks, uncertainties, and assumptions that could cause actual results to differ materially. Readers should not place undue reliance on such statements. The Company’s officers, directors, and insiders may hold securities of RZOLV and therefore have a financial interest in the Company’s performance. Readers are encouraged to review RZOLV’s public disclosure documents available on SEDAR+ for a discussion of material risks and assumptions. Neither the TSX Venture Exchange nor its Regulation Services Provider has reviewed or approved the contents of this article.