The Visoke complex is one of the main Quaternary volcanic centres of the Virunga Range, located north of lake Kivu. Mineralogical (microprobe) data are given for two representative leucitite lavas; one sample contains a complex coarse-grained xenolith (phlogopite, diopside, leucite, titanomagnetite, perovskite and apatite) and megacrysts of pyroxene, phlogopite and olivine scattered in fine-grained leucite-rich host lava. Compared with the typical leucite-dominated, low-pressure phenocryst assemblage of the two samples studied, the chemical trends of ferromagnesian crystals suggest an earlier igneous event (high-pressure phenomenon) strongly related to the leucite-bearing magma suite.