Non-Cyanide Gold Leach Reaches Pilot — Watch the Gap: what changes now
Aurquest Alaska funded equipment costs and delivered 2.15 metric tons of high-grade gold concentrates for initial runs Decision Focus RZOLV…
The Mining Operations Director - November 3, 2026
Aurquest Alaska funded equipment costs and delivered 2.15 metric tons of high-grade gold concentrates for initial runs
Decision Focus
RZOLV Technologies and Aurquest Alaska began construction this month on a pilot plant in North Vancouver, British Columbia, to test a water-based, non-cyanide leaching system against gold-bearing black sand concentrates from Alaska placer operations. The pilot targets commissioning in Q1 2027. For Mining Operations Directors managing placer gold assets — or overseeing gravity recovery circuits that leave fine gold stranded in heavy mineral concentrates — the operating signal is this: a non-cyanide processing route is now moving from independent lab validation toward integrated pilot demonstration, with a proposed commercial toll-processing facility in Nome, Alaska, as the stated end goal.
90-Second Brief
As the week closes, rZOLV’s proprietary water-based leaching solution was independently tested by SGS Canada, returning 98.7% gold dissolution from oxide concentrates in 96 hours and 89.4% from sulfide concentrates. Cyanide benchmarks in the same tests were 99.9% and 90.7% respectively. The North Vancouver pilot will integrate RZOLV’s leaching technology with EMEW electrowinning cells to demonstrate a full recovery circuit, from concentrate feed through to a refinery-ready product, rather than leach performance in isolation. Aurquest Alaska funded equipment costs and delivered 2.15 metric tons of high-grade gold concentrates for initial runs.
What Is Really Happening?
Gravity recovery circuits at placer gold operations are effective at separating coarse gold but routinely leave measurable fine gold locked in heavy mineral concentrates dominated by ilmenite, magnetite, garnet, rutile, and monazite. Historically, the two practical extraction routes for this residual gold were mercury and cyanide — both carrying regulatory, safety, and community-acceptance burdens that have made them unworkable for smaller or more remote placer operations, particularly in jurisdictions with tightening environmental oversight.
RZOLV’s approach attempts to close that gap with a water-based leaching agent that dissolves gold and other metals, which are then recovered through conventional downstream steps — carbon adsorption, electrowinning, or ion exchange. The SGS Canada results indicate the leach performance is genuinely competitive for oxide-type concentrates and meaningfully close for sulfide types. What has not yet been demonstrated is whether the full integrated circuit — leach, metal recovery, and solution recycling — achieves those results at pilot throughput, at acceptable reagent consumption, and with a cost structure that supports commercial operation in a remote Alaskan setting.
The North Vancouver facility is specifically designed to generate that operating data. RZOLV President and CEO Duane Nelson described the pilot’s purpose as moving from testing individual materials to demonstrating “an integrated recovery process at pilot scale, including metal recovery and the recycling and reuse of process solutions.” That framing matters for operators: the SGS number is a leach efficiency figure, not a project economics figure. The gap between the two is precisely what the pilot must bridge.
Why It Matters for Mining Operations Directors
For placer gold operations in Alaska and comparable jurisdictions, the conventional path for black sand concentrates is either toll-treating them through a cyanide-capable facility or stockpiling them as uneconomic residues — options that either add transport and processing cost or leave recoverable value permanently stranded. If RZOLV’s integrated pilot demonstrates recovery performance and solution-recycling efficiency at scale, it would represent a credible processing alternative for material that currently generates no revenue.
The toll-processing model proposed for Nome — where a commercial plant would accept concentrates from multiple placer operations across the region — lowers the capital barrier for individual operators. Rather than installing and permitting on-site leach infrastructure, an operations director with placer assets could access regional processing capacity under a toll arrangement. That model shifts permitting complexity and capital exposure to the centralized facility, changing the decision calculus for smaller-volume producers considerably.
The sulfide concentrate result warrants separate attention. An 89.4% gold extraction against cyanide’s 90.7% is a narrow gap under controlled lab conditions. Whether that margin widens, holds, or closes under pilot throughput and solution-recycling cycles is among the most practically significant data points the Q1 2027 commissioning will need to produce.
Forward View
If the North Vancouver pilot runs on schedule and produces the integrated circuit data RZOLV requires, the next decision point is whether the Nome commercial facility advances from negotiation to construction. That progression depends on both technical performance from the pilot and execution of a joint venture agreement between RZOLV and Aurquest that has not yet been formalized.
RZOLV has also indicated the technology’s applicability extends beyond placer gold concentrates to mineral ores, recycled materials, and other concentrate types. If pilot performance supports that broader claim, the technology could become relevant to operations managing complex or mixed-sulfide concentrates at non-placer assets — but that application remains speculative until pilot data is made available.
Operations directors in jurisdictions where cyanide use faces intensifying regulatory scrutiny should track this pilot’s results as a potential input to future processing design decisions, even if commercial adoption is several years out.
What Is Still Uncertain
The pilot has not yet run. The Q1 2027 commissioning target could slip, and RZOLV has not published a timeline for releasing pilot results. The 96-hour leach duration confirmed in SGS lab tests has not been evaluated against commercial throughput requirements — faster cycle times would improve economics but may affect recovery rates. Reagent consumption across multiple solution-recycling cycles, a key operating cost driver, is among the explicit unknowns the pilot is designed to address.
The Nome commercial facility remains conditional on successful pilot outcomes and a joint venture that has not been executed. Cost per ounce recovered at commercial scale is not established. The CAD 121,000 NRC-IRAP grant confirms government-level interest but is modest relative to the capital required for a commercial facility — the funding structure beyond the pilot stage is not publicly confirmed.
One Question for Your Team
If a regional toll-processing facility using non-cyanide leach technology were operating near your placer assets within three years, how many tonnes of black sand concentrate currently classified as uneconomic residue would qualify for reprocessing — and what revenue assumption are you currently assigning to that material?
The Mining Operations Director
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