Company: SQM
Filing Date: 2025-04-24
Form Type: 20-F
Source: 0000909037-25-000020
Chunk: 91

Company: CHEMICAL & MINING CO OF CHILE INC
Filing Date: 2025-04-24
Form: 20-F
Item: Item 4A
Chunk 91
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 mineral resource with the highest level of geological confidence; quantity and grade or quality are estimated on the basis of conclusive geological evidence and sampling. The level of geological certainty associated with a measured mineral resource is sufficient to allow a QP to apply modifying factors in sufficient detail to support detailed mine planning and final evaluation of the economic viability of the deposit.
•Indicated resource. That part of a mineral resource with a level of geological confidence between that of measured and inferred resources; quantity and grade or quality are estimated on the basis of adequate geological evidence and sampling. The level of geological certainty associated with an indicated mineral resource is sufficient to allow a QP to apply modifying factors in sufficient detail to support mine planning and evaluation of the economic viability of the deposit.
•Inferred resource. That part of a mineral resource with the lowest level of geological confidence; quantity and grade or quality are estimated on the basis of limited geological evidence and sampling. The level of geological uncertainty associated with an inferred mineral resource is too high to apply relevant technical and economic factors likely to influence the prospects of economic extraction in a manner useful for evaluation of economic viability.
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Geologists and mining engineers who are QPs have prepared estimates of caliche ore resources and reserves. The resource and reserve figures presented below are estimates and may be subject to modifications due to natural factors that affect the distribution of mineral grades, which would, in turn, modify the recovery of nitrate and iodine. Therefore, no assurance can be given that the indicated levels of recovery of nitrates and iodine will be realized. Estimates of ore resources and reserves are based on evaluations, performed by engineers and geologists, of assay values derived from sampling of drillholes and additional samples. Drillholes have been made at different spaced intervals suitable to defining a resource. Drill patterns begin at 400 x 400 meters and spacing is reduced to 200 x 200 meters, 100 x 100 meters, 100 x 50 meters, and 50 x 50 meters. The caliche ore is unique and different from other metallic and non-metallic minerals. Caliche ore is found in large horizontal layers at depths ranging from one to four meters and has an overburden between zero and two meters. This horizontal layering is a natural geological condition that allows resource estimates to be made with high confidence in the continuity of the caliche bed, based on surface geological