The experts from Makerere University (Mak) and the Royal Institute of Technology (KTH) evaluated three mineral deposits for the production of fireclay refractories in Uganda and found that the Mutaka kaolin deposit in Uganda is of extraordinary quality. Ten tons of raw kaolin was mined at the Mutaka deposit and shipped in a container to STFI-Packforsk, Sweden. The kaolin was first dry sieved in a shaker to remove sand, mica and large particles. The sieved material was mixed with fresh water to a dry content of 15% and hydrocycloned to separate and remove coarse particles. The paper machine trials were carried out at STFI-Packforsk on the EuroFEX paper machine. The results indicate that the potential of exploiting the Mutaka kaolin deposit for paper filling is high. Paper filled with Mutaka clay resulted in a slightly lower opacity, however, with an optimized particles size distribution, this could be improved.