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Item type:Item, Access status: Open Access , An evaluation of the use of high-resolution RGB and multispectral imaging as a potential tool for drill-core logging of the rocks of the Bushveld Complex(University of the Free State, 2025) Mabogo, Nomonde Shantel Tshiwela; Roelofse, Frederick; Clark, MartinCore recovery drilling remains a fundamental component of mineral exploration in the Bushveld Complex of South Africa, which hosts the world’s largest platinum-group element reserves within the world’s largest layered intrusion, the mafic to ultramafic Rustenburg Layered Suite. Manual logging of extensive drill-core intervals is time-consuming and inherently subjective, often limiting the precision of lithological and mineralogical interpretations. This study assesses spectroscopic drill-core logging techniques, such as RGB to-grayscale and visible to near-infrared (VNIR) multispectral imaging (400-842 nm), applied to the Rustenburg Layered Suite drill-core as potential tools for cost-effective drill-core logging of the major lithologies and minerals of the Rustenburg Layered Suite. High-resolution RGB images were converted to grayscale using the luminosity method, and grayscale digital number (0-255) statistics, median and skewness were analysed for lithological classification. The grayscale approach distinguishes chromitite and anorthosite through contrasting histogram skewness, with median-based validation correctly classifying 3% of anorthosite samples and 0% of chromitite, the latter is due to limited representation in the training dataset and that training and validation chromitite samples differ in the proportion of dark and lighter crystals. In contrast, gabbronorite and pyroxenite proved more challenging to differentiate, reflecting their broad compositional ranges and overlapping plagioclase pyroxene assemblages, with 19% gabbronorite validation sites and 44% pyroxenite validation sites being either a gabbronorite or pyroxenite. Additionally, the weighting of the green channel in the luminosity-based grayscale conversion can shift darker pixels toward higher grayscale values, potentially leading to the misclassification of dark lithologies as lighter-coloured lithologies. Thus, this approach proved less effective for reliable lithological classification across the dataset. VNIR multispectral imaging (475-842 nm) enables classification of major minerals such as pyroxene, plagioclase, and chromite, with spectral library correlations improving accuracy by identifying minerals prone to misclassification. The results show that 40% of pyroxenite samples contained over 90% pyroxene, 12% of anorthosite samples contained over 90% plagioclase, 71-75% of gabbronorite samples exhibited mixed plagioclase-pyroxene proportions within the 10-90% compositional range, and all chromitite samples contained more than 45% chromite. Results also reflect expected mineralogical trends, with mafic rocks showing higher mafic mineral content and anorthositic rocks dominated by felsic minerals.Item type:Item, Access status: Open Access , Masculinity and Fatherhood: A Narrative Study of South African Black Men Living in Mangaung(University of the Free State, 2024) Velelo, Nontombi Lenah; Rau, Asta; Coetzee, Jan K.Item type:Item, Access status: Open Access , The complexities of translator education in Ghana: exploring a human capabilities approach to curriculum design(University of the Free State, 2024) Dakey, Linda Esinam; Marais, Kobus; González-Davies, MariaItem type:Item, Access status: Open Access , Representations of trauma in poetic parallelisms of the Biblical Hebrew Book of Job: a complexity theoretical analysis(University of the Free State, 2024) Nortier, Hermias Hendrik Sutherland; Naudé, J.A.; Miller-Naudé, C.L.Item type:Item, Access status: Open Access , Morphosyntactic aspects of the infinitive construct in Qumran Hebrew(University of the Free State, 2024) Rampanjato, Fianarana Andriamahatozo; Miller-Naudé, C.L.; Naudé, J.A.Item type:Item, Access status: Open Access , Emerging from Crisis: Representation of Childhood Identities From Selected Zimbabwean Short Stories of the Third Chimurenga Era(University of the Free State, 2024) Mawire, Primrose Rufaro; Ngara, K.M.; Manase, I.Item type:Item, Access status: Open Access , Cosmologies of Madness: Exploring Representations of Madness in Contemporary African Literary and Cultural Texts(University of the Free State, 2024) Fingson, Kundai Watson; Ngara, Kudzayi M.; Nyambi, OliverItem type:Item, Access status: Open Access , Narratiewe pastorale spel en gemarginaliseerde gemeenskappe(University of the Free State, 2024) Van Schalkwyk, Hester Helena; Van den Berg, Jan-AlbertItem type:Item, Access status: Open Access , Imaging prosperity in African Christianity: a practical theological case study of urban congregations in Lusaka, Zambia(University of the Free State, 2024) Banda, Daniel Sandford; Van der Watt, GideonItem type:Item, Access status: Open Access , Intersemiotic Bible translation for an orally dominant culture: the case of translating Lamentations into Nsenga(University of the Free State, 2024) Nyirenda, Gift; Naudé, Jacobus A.; Miller-Naudé, Cynthia L.