Nutrien's February 2025 technical report on Cory explains why its mill recovery runs below Nutrien's other plants: more of its output, at one point all of it, has come from the crystallization process.
The National Instrument 43-101 Technical Report on the Cory Potash Deposit (KL 103 C), dated February 20, 2025, covers Nutrien Ltd.'s Cory operation just outside Saskatoon, Saskatchewan. Cory has mined and concentrated potash ore since 1968. Its mill uses both flotation and crystallization to make near-pure potassium chloride (KCl), and its product range is wider than at most potash mills: granular, standard and soluble potash and chicklets, for industrial, agricultural and feed uses.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Report date | February 20, 2025 | Not applicable | NI 43-101 technical report, Nutrien Ltd. |
| Operator | Nutrien Ltd. | Not applicable | Qualified persons: Jodi Derkach and Craig Funk |
| Production since | 1968 | Not applicable | Continuous sales since mining began |
| Finished potash, 2022 | 1.888 | Mt | 61.58% K2O average grade |
| Finished potash, 2023 | 1.493 | Mt | 61.74% K2O average grade |
| Finished potash, 2024 | 2.113 | Mt | 61.50% K2O average grade |
| Mill recovery, past decade | 72.3 to 83.0 | % | Average 77.8% |
| Concentration methods | Flotation and crystallization | Not applicable | Larger crystallization share than other Nutrien plants |
| High-voltage power capacity | 52 | MVA | Utility can meet projected demand |
| Brine inflow | About 337 | L/min | Four collection points, plus about 40 L/min into the shafts |
Overview
Raw ore is processed on surface at the Cory mill, where flotation and crystallization circuits produce concentrated finished potash that is shipped to North American and offshore markets. Most product moves by rail, some by truck.
Production was 1.888 million tonnes in 2022, 1.493 million tonnes in 2023 and 2.113 million tonnes in 2024, at grades between 61.50% and 61.74% K2O. Mill recovery over the past decade ranged from 72.3% to 83.0% and averaged 77.8%. The report explains that Cory's recoveries have historically been lower than at Nutrien's other plants because a larger portion of its production, and at one point all of it, came from crystallization. It anticipates no fundamental milling problems in the foreseeable future, and circuit optimization testing continues.
Key Process Stages
Ore processing on surface. Potash ore is processed in the Cory mill on surface, using the flotation and crystallization milling methods shown in the report's simplified flow diagram.
Flotation and crystallization. Both methods concentrate the ore into near-pure KCl. Crystallization has carried a larger share of Cory's output than at Nutrien's other plants, which the report gives as the reason for Cory's lower recoveries.
Product finishing. The mill makes granular, standard and soluble potash and chicklets for industrial, agricultural and feed applications.
Additional Interesting Data and Summary
Fresh water for milling comes by waterline from the South Saskatchewan River, about 10 km away, under a Water Security Agency licence. High-voltage power capacity is 52 MVA. Saskatoon, the nearest city, is 7 km from the site.
Cory has seen numerous small brine inflows over more than 50 years of mining. Four brine collection points are active, with a combined flow averaging about 337 litres per minute, and inflow into the shafts is estimated at 40 litres per minute. The brine is pumped to surface and disposed of in the tailings management area.
In summary, Cory is a long-running flotation and crystallization potash mill whose larger reliance on crystallization goes with a lower ten-year average recovery of 77.8%.
Key Processes
- Underground potash ore processed on surface
- Flotation
- Crystallization, a large share of output
- Granular, standard and soluble KCl and chicklets
- Shipment by rail and truck
Source: Nutrien Ltd., National Instrument 43-101 Technical Report on Cory Potash Deposit (KL 103 C), Saskatchewan, Canada, February 20, 2025.
Earlier report summaries
Earlier versions of this profile, based on older technical reports, are retained below for source traceability. Dates and figures reflect each report’s own effective date and are superseded by the current information above.
Cory — 2018 Technical Report
This 2018 technical report describes the Cory potash facility's shift to a dedicated crystallisation plant with 0.8 Mt/y capacity, producing only white potash products since October 2017.
Report context
The Cory potash operation in Saskatchewan, Canada, has produced finished potash products since 1968. After a period of major expansion between 2008 and 2011, followed by operational curtailments in 2013, the facility reverted in October 2017 to a pure crystallisation plant producing only white potash products at a curtailed capacity of 0.8 million tonnes per year. This February 2018 technical report documents the processing route at that time, noting that Cory's long operational history,112.632 million tonnes of ore mined and hoisted to produce 35.486 million tonnes of finished product from 1968 to December 2017,means basic prospective metallurgical testing is not considered relevant.
Processing route
Crystallisation method and products
The Cory mill uses crystallisation to concentrate potash ore into finished products. A simplified process flow diagram exists in the report (Figure 23) but no equipment, flowsheet stages, or detailed process descriptions are provided in the cited sections. The method produces concentrated white potash products that are near-pure KCl.
Products include:
- High-grade specialised white soluble potash
- White granular
- Chicklets
- Prills
These products serve industrial, agricultural, and feed applications and are shipped to markets in North America and offshore.
Ore source and production history
Raw potash ore is processed on surface after mining. Over the 49 years from start-up to December 2017, the cumulative finished product from 112.632 million tonnes of ore represents a long-term operational recovery record. The report states that no fundamental potash milling problems are anticipated based on this long-term experience with potash geology and actual mill recovery.
Ongoing optimisation
Quality control testing and monitoring aimed at fine-tuning and optimising potash milling and concentrating processes is conducted continually at Cory, as at all Nutrien minesites and research facilities. Test work to optimise circuit performance and ensure product quality is carried out on an ongoing basis.
Key reported parameters
| Parameter | Value | Basis |
|---|---|---|
| Nameplate capacity (2011 expansion) | 3.0 million tonnes finished potash products per year | Historic design |
| Operating capability post-December 2013 curtailment | 1.4 million tonnes per year | Announced operational change |
| Operating capacity post-October 2017 curtailment | 0.8 million tonnes per year | Actual operating capacity |
| Finished production 2015 | 1.508 million tonnes | Actual |
| Finished product average grade 2015 | 61.45% K₂O | Actual |
| Finished production 2016 | 1.241 million tonnes | Actual |
| Finished product average grade 2016 | 61.56% K₂O | Actual |
| Finished production 2017 | 0.988 million tonnes | Actual |
| Finished product average grade 2017 | 61.96% K₂O | Actual |
| Mill recovery rate range (past decade) | 66.4% – 75.6% | Actual |
| Average mill recovery rate (past decade) | 72.0% | Actual |
| Cumulative ore mined (1968 to December 2017) | 112.632 million tonnes | Actual |
| Cumulative finished product (1968 to December 2017) | 35.486 million tonnes | Actual |
Project website: https://www.nutrien.com/about/our-business/locations?tab=potash
Project website: https://altiusminerals.com/royalties/cory/
Technical qualifications
This profile is based solely on the February 20, 2018 technical report for the Cory Potash deposit (KL 103B), Saskatchewan, Canada, prepared for Nutrien Ltd. The cited processing information comes from Sections 13.0 and 17.0 of the Markdown conversion of that report. Key limitations include: the simplified process flow diagram (Figure 23) is referenced but not reproduced in the cited text, so no equipment, flowsheet stages, or process chemistry details are available from these sections; the 3.0 Mt/y nameplate from the 2008-2011 expansion is historic and does not represent operating capacity in 2018; only finished product tonnages and K₂O grades are reported (not ore throughput or KCl content); and no tailings, water, or reagent data are provided in the cited sections. The report explicitly states that basic mineralogical processing and prospective metallurgical testing are not relevant given the long operational history; ongoing optimisation testing is described in general terms only.
Source: Nutrien Ltd., Cory Potash, National Instrument 43-101 Technical Report on Cory Potash Deposit (KL 103B), Saskatchewan, Canada, February 20, 2018, Sections 13.0 and 17.0. of that report.
