| Summary: | Drill core logging in the mining industry has traditionally been done by geologists and technicians using basic tools such as a loupe, knife, and magnet, amongst others. The descriptions are usually time-consuming, qualitative, subjective and require the use of expensive complementary techniques, i.e. chemical assays, for acquisition of precise information. Mineralogical and textural relations valuable for the beneficiation stages in a geometallurgical approach are usually not considered; therefore, techniques that allow automated logging and a more detailed characterisation of the ores are necessary for a mineralogical-oriented logging system. Hyperspectral imaging has been recently used in the iron ore industry since the main iron minerals (i.e. hematite, goethite, jarosite) are easily distinguished with this technique. Hyperspectral imaging in the sulphide and gold ore industry is not as extended and is focused on an exploration level, as alteration minerals indicators of the mineralized areas are easily traceable. However, no direct detection of sulphide minerals is at the moment possible with the available commercial techniques. Possible sulphide discrimination and characterisation of their textural relations during logging would allow better knowledge of the ore and a better behaviour forecasting in the beneficiation process. Tests for sulphide detection have only been performed with microwave heating under infra-red thermography for ore gradation and sulphide detection purposes.This Master Thesis presents the results of a mineralogical and textural characterisation of three different sulphide-bearing ores of both orogenic gold and polymetallic VMS deposits from the northern Fennoscandian Shield. A detailed mineralogical and textural characterisation using optical microscopy, SEM-EDS and XRD is included for the evaluation of newly tested techniques. Hyperspectral imaging in different bandwidths and resolutions is evaluated for mineral detection. For the orogenic gold ores, hyperspectral imaging could be ...
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