Sodium Cyanide Supply: Briquette Versus Liquid, Detox Cost and the Permitting Timeline
Gold operators tend to price cyanide per kilogram of reagent and discover the real cost at the detox circuit. The reagent that leaches the ore is only half the bill; the chemistry that destroys it before discharge is the other half, and that half scales with throughput rather than with ore grade.
This note is for metallurgists and procurement leads buying sodium cyanide for gold and silver operations. It covers the solid versus liquid decision at remote sites, why ore chemistry changes consumption more than suppliers admit, and the contract terms that survive a permitting timeline measured in years. The volume structure of the category is set out in this analysis of the sodium cyanide market, which puts the segment near USD 345 million by the early 2030s.
Detoxification cost, not reagent price, is what separates a low-cost cyanide supply from an expensive one
Between 2024 and 2026, tighter cyanide discharge limits in several Australian and Canadian jurisdictions lifted consumption of detoxification reagents — hydrogen peroxide, and sulphur dioxide with air — by fifteen to twenty-five percent. That is a recurring line item, not a capital cost, and it moves with tonnage processed.
Mid-tier Latin American miners have reported twelve to eighteen percent increases in International Cyanide Management Code compliance and detoxification costs over a similar period. A buyer comparing two reagent quotes on a per-kilogram basis is therefore comparing the smaller half of the number.
The workable comparison is cost per tonne of ore processed, with detox reagents, compliance monitoring and effluent testing included. Ask each supplier for that figure against your ore type; a supplier who cannot discuss it is selling commodity, not supply.
Why high-copper refractory ore costs more than the assay suggests
Work published in Minerals Engineering in 2025 found that high-copper refractory gold ores consumed eight to fifteen percent more cyanide than standard oxide ores. The penalty is not purely chemical. Recovery also decayed measurably across forty-eight to seventy-two hour leach cycles, which forces metallurgists to rework reagent budgets and to weigh pre-treatment options before a recovery target can be held.
This matters for procurement because consumption forecasts are usually built from historical site data on oxide ore. When the pit transitions into a refractory zone, the same contract volume delivers fewer recovered ounces, and the shortfall arrives without any change to the reagent price.
Model the transition explicitly. If the life-of-mine plan includes a sulphide or refractory phase, the cyanide contract should carry a volume band that accommodates the higher consumption rather than a fixed annual quantity with penalty clauses on both sides.
Solid briquettes or liquid: the logistics decide it
Liquid sodium cyanide is cheaper per unit of contained reagent where a plant exists nearby and the road is ordinary. On high-altitude routes in Peru and Chile, liquid freight premiums have reached eighteen percent, and that changes the arithmetic.
Solid briquettes carry their own handling requirements: dissolution capacity, dust control, a dedicated mixing area and the labour to run it. At a remote operation, that infrastructure is often already justified by the freight differential alone.
The decision is not permanent, but it is sticky, because dissolution equipment and permits are site-specific. Decide it against the full life-of-mine logistics profile rather than the current road condition, and keep the contract convertible if the mine plan shifts.
What a permitting timeline does to your supply strategy
Environmental permitting delays have stretched localized liquid plant timelines to eighteen to thirty months in some jurisdictions. If your operation assumes an on-site or near-site liquid supply will be available at start-up, a two-year slip in that permit becomes a two-year dependence on delivered solid reagent.
The practical response is to secure multi-year, index-linked supply agreements rather than spot coverage, and to keep a qualified second source even when the primary contract has volume headroom. Cyanide is not a reagent a mine can run short of for a week.
On the pricing side, index linkage protects both parties from a fixed-price contract that becomes unworkable after a freight or energy shock. The index should be published, specific to the reagent, and reviewable on a defined cycle.
Where the reagent sits in the wider metals chain
Cyanide consumption follows gold and silver output, and both follow ore grade, mine life and the capital available for pre-treatment. A buyer who tracks only the cyanide market misses the demand signal that actually predicts availability: the project pipeline in the producing regions.
That chain is worth mapping before a multi-year commitment, because supplier capacity additions are decided against the same pipeline. A practical starting point is this map of non-ferrous and alloy raw material sourcing, which sets out where the upstream concentration sits.
Why the second source matters more than the volume discount
A cyanide shortfall stops the leach circuit within days, and no volume discount compensates for that. Yet second-source qualification is the line most often cut when a primary supplier offers a step discount above a stated tonnage.
The exposure is not only supplier failure. It is also the wet season, the border, and the road. A single qualified source means every logistics disruption lands directly on production, and the emergency premium paid to recover is always larger than the discount that bought the single-source position.
Qualify the second source on a small annual volume and keep it live. The cost of maintaining a qualified alternative is a fraction of one week of lost leach throughput, and it changes the negotiating position on every renewal.
What to inspect when the delivery arrives
Assay the delivery, do not accept the certificate. Take three samples per lot: one from the top of the container, one from the middle after partial discharge and one from the base. Compare cyanide content across the three. A spread above one percentage point says the lot segregated in transit or absorbed moisture, and moisture in briquettes is the failure mode that reaches the leach tank as reduced reagent and unexpected hydrogen cyanide risk in the mixing area.
Record briquette dimensions and crush strength on the first lot and on every tenth lot after. Fines generate dust in handling and dissolve too quickly in the mixing box, which changes the strength of the solution actually delivered to the leach circuit.
Keep a retained sample of every lot for the life of the mine plan plus the audit period. When a compliance auditor asks what reagent entered the circuit in a given quarter, the retained sample is the only defensible answer.
Frequently asked questions
Should a remote mine buy solid or liquid sodium cyanide?
Solid, in most high-altitude and long-haul cases, because liquid freight premiums have reached eighteen percent on some routes and the dissolution infrastructure is a one-off cost. Near a plant with ordinary logistics, liquid usually wins on unit cost.
How much does ore type change cyanide consumption?
High-copper refractory gold ores consumed eight to fifteen percent more than standard oxide ores in published 2025 work, with measurable recovery decay across forty-eight to seventy-two hour leach cycles.
What is the biggest hidden cost in a cyanide supply contract?
Detoxification. Tighter discharge limits lifted detox reagent consumption by fifteen to twenty-five percent in several jurisdictions, and that cost scales with throughput rather than with reagent price.
How long should a supply agreement run?
Long enough to cover a permitting slip of eighteen to thirty months for localized liquid capacity, with a published index and a defined review cycle. Keep a qualified second source regardless of contracted volume.
What to change in the next cyanide tender
Require cost per tonne of ore processed with detox reagents included, not price per kilogram. State the ore transition in the volume band rather than the base case. And write the sampling protocol — three points, one percentage point spread, retained samples — into the acceptance terms before the first delivery arrives.