In mines in Katanga region of the Democratic Republic of Congo (DRC), cobalt is commonly recovered from oxyhydroxide minerals (e.g. heterogenite, asbolane) using a sulfuric acid leach under reducing conditions. However, most of the leaching operations show yields of Co, below 80% so the current study focused on determining the reasons for the recovery shortfall. A range of samples were investigated comprising a detailed mineralogical characterization of five concentrate and leached samples from different mine plants in the Katanga region: namely Kalukuluku, Mutanda, Mabaya, Kamwali and Fungurume mines. The analyses were carried out prior to and after leaching treatments using a combination of chemical (ICP-AES) and mineralogical techniques (XRD, automated mineralogy, SEM-EDS and X-ray mapping). The results revealed that heterogenite and asbolane occur in samples both prior to and after leaching: this confirms the ineffective leaching of these minerals or/and the presence of Co-bearing refractory minerals and other phases inhibiting the diffusion of leachate. SEM-EDS and X-ray mapping of leached samples showed that both heterogenite and asbolane are commonly finely intergrown with clays and Fe-oxyhydroxides (FOH). These outcomes are in agreement with automated mineralogy results for the Co deportment, showing that Co is mainly hosted in: (a) pure heterogenite particles, (b) heterogenite intergrown with other minerals, (c) fine-grain heterogenite (<= 1 mu m) enclosed in clays, and (d) clays or/and FOH adsorbing Co in the structure. The Co recovery inefficiency is a result of the mineralogical complexity of the ores, making the current processing strategy sub-optimal. In conclusion the two main reasons for the incomplete recovery are: firstly mineral liberation issues and secondly the presence of un-recoverable elemental Co within the structure of refractory phases.