Extensive potash deposits are found in the southern half of the Province of Saskatchewan. The potash ore is contained in a predominantly rock salt formation known as the Prairie Evaporites. The Prairie Evaporites deposits are bounded by limestone formations and contain the potash beds.

Esterhazy utilizes shaft mining. Traditional potash shaft mining takes place underground at depths of over 1,000 meters where continuous mining machines cut out the ore face and load it onto conveyor belts. The ore is then crushed, moved to storage bins and hoisted to refineries above ground.

The underground mining operation uses a conventional room and pillar mining technique which consists of a series of equally-spaced rooms interconnected by access tunnels. The ore is mined with a continuous mining machines consisting of rotating heads studded with tungsten carbide steel bits. The continuous miners feed the ore on to an extensible belt conveyor attached to the rear of the miner. The extensible conveyors feed a number of conveyor belts which carry the ore to storage bins. From the storage bins, the ore travels by conveyor to the crushers which reduce the ore into pieces no larger than about six inches in diameter. Following crushing, the ore is transported by conveyor belt to the shaft skips. Each of the two shafts is equipped with a pair of ore-hoisting skips which operate in tandem - one skip moving up to the surface to be unloaded, while the other is on its way down to pick up more ore.

The underground workings of the K1 and K2 mine are connected. Four different potash products are produced between the two mills. The four products are classified according to size or grade. These products, in descending order from largest to the smallest, are: Compacted Granular, Natural Crystal Granular, Standard, and White Muriate. Various production processes are utilized in making these products, but all start with crushing the ore into particles less than 9.5 mm. Reduced to this size, the ore separates into individual crystals of either potassium chloride or sodium chloride. The crushed ore is mixed with brine and screened. Particles which are larger than 1.7 mm are diverted to heavy media and particles smaller than 1.7 mm drop through the screen and go on to flotation.

The heavy media process produces Natural Crystal potash. In this process, the particles of potassium chloride and sodium chloride are introduced into a brine solution to which magnetite has been added. The specific gravity of potassium chloride is less than that of sodium chloride, and the magnetite increases the brine’s specific gravity to a point midway between that of potassium chloride and sodium chloride. In this heavy media solution, and when centrifugal force is applied in a cyclone, the potassium chloride floats to the top of the cyclone and the sodium chloride and most other impurities sink to the bottom of the cyclone. The potassium chloride is then washed to remove the last of the impurities and is de-brined and dried.

The flotation process is used to separate particles smaller than 1.7 mm. This process produces the standard and special standard grades. In the flotation process, the particles are slurried with brine and then pumped through a desliming circuit. Desliming utilizes screens and cyclones to remove insoluble materials and excess brine. After desliming, the ore is conditioned with various chemical reagents which coat the particles of potassium chloride but will not adhere to the particles of sodium chloride. This conditioned ore is slurried in brine and fed into flotation cells. Air is injected into the slurry, forming bubbles which attach themselves to the coated particles of potash and float them to the surface, where they are skimmed off as product and de-brined and dried. The sodium chloride sinks to the bottom of the tank; from there it is drawn off and disposed of as tailings.

Granular grade potash is made by the high-pressure compacting of a mixture of standard and special standard sizes. The compacting of these two products produces a solid slab of potash which is then crushed and screened to size.

Potash particles that are too small to be recovered in original flotation are recovered separately in a scavenger flotation circuit. These scavenger recoveries plus the potassium chloride dust that has accumulated in the various drying, screening, and compacting procedures are used to produce White Muriate. Production is by a crystallization process in which the fines are first dissolved in heated brine. Then three stages of cooling transform the fines into larger and purer crystals of potassium chloride.

As in the other production procedures, the final step is debrining and drying.

Once dried and screened to size, all final products are dispatched to a loadout facility or inventory storage bins.