Chemical Staining Techniques for Drill Core Characterization

Accurate mineralogical identification is critical across the mining value chain from host rock characterization and alteration mapping, to mineral processing and environmental management. Advanced techniques for rapid mineralogical identification in drill core including hyperspectral scanners (e.g., HyLogger™, Corescan™) are becoming increasingly available to the mining industry. However, their high associated costs and logistical problems with deploying to field sites means that these techniques are not yet ubiquitously available. Mineral specific chemical staining techniques for carbonate and feldspar minerals offer a rapid and cheap alternative to hyperspectral scanning and more traditional mineral identification techniques (e.g., X-ray diffractometry, electron microprobe analysis). This contribution provides an updated review of chemical staining procedures for carbonate and feldspar minerals and how they can be used to map the distribution and texture of these minerals in drill core. Used under controlled health and safety conditions, chemical staining of drill core can assist with identification and mapping of these minerals during exploration activities (i.e., resolving alteration assemblages), feasibility studies (i.e., indicating ore grindability and flotation cell pH) and environmental assessments (i.e., domaining short and long term acid neutralization capacity).