Company: SQM
Filing Date: 2025-04-24
Form Type: 20-F
Source: 0000909037-25-000020
Chunk: 66

Company: CHEMICAL & MINING CO OF CHILE INC
Filing Date: 2025-04-24
Form: 20-F
Item: Item 4
Chunk 66
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, iodine and potassium; 
•brines from the Salar de Atacama, which contain potassium, lithium, sulfate, boron and magnesium; and
•spodumene deposits from the Mt. Holland project in Western Australia, which contain lithium.
Caliche Ore Deposits
Caliche ore deposits are located in the First and Second Regions in northern Chile. During 2024, our mining operations were concentrated in the First Region where we mainly worked in the mining sectors Tente en el Aire, Mina Oeste, Hermosa, Mina Sur and Torcaza, and in the Second Region at the Pampa Blanca site. Operations at the El Toco mine (which is part of the Maria Elena site) and the Pedro de Valdivia site were suspended in November 2013 and November 2015, respectively, in an effort to optimize our production facilities with lower production costs.
Caliche ore is found under a layer of barren overburden in seams with variable thickness from one to four meters, and with the overburden varying in thickness between zero and two meters.
Before proper mining begins, the exploration stage is carried out, including complete geological reconnaissance, sampling and drilling caliche ore to determine the quality and characteristics of each deposit. Treatability tests are performed at a pilot plant. Drill-hole samples are properly identified and tested at our chemical laboratories. With the exploration information on a closed grid pattern of drill holes, the ore evaluation stage provides information for mine planning purposes. Mine planning is done on a long-term basis (ten years), medium-term basis (three to five years) and short-term basis (one year). Once all of this information has been compiled, detailed planning for the exploitation of the mine takes place.
The mining process generally begins with bulldozers first removing the overburden in the mining area. This process is followed by an inspection and review of the drill holes before production drilling and blasting occurs to break the caliche seams. The ore is loaded onto off-road trucks, which take it to the leaching heaps to be processed.
During 2024, SQM used four continuous mining equipment systems to replace the drilling and blasting process for mining some of the caliche ore and obtaining a smaller ore size (under 6 ½ inches) that allows a better metallurgical recovery.
The run of mine ore is loaded in heaps and leached with water to produce concentrated solutions containing iodine, nitrate and potassium. These solutions are treated at our iodide plants where iodine