Using a marble sample from the central Damara Orogen (South West Africa) the determination of the temperature of metamorphism was undertaken with the help of the dolomite-calcite solvus geothermometer for unmixed magnesian calcite crystals. There is good agreement between the results obtained by electron microprobe analysis and by point count analysis of the surface area of exsolved dolomite grains in magnesian calcite. Accordingly, the temperature reached during metamorphism of the investigated marble occurence, based on the dolomite-calcite solvus determination of Goldsmith and Newton (1969), was 620 °C.