resources of Zambia. In Phosphate deposits of the

chromatography, so direct comparison with out electron microprobe data should be made with caution. Acknowledgements'. This study forms part of a project on African carbonatitcs funded by the Overseas De-velopment Administration, UK. Improvements o the manuscript were suggested by F. Wall and J. F. W. Bowles. Permission to publish was granted by the Director, British Geological Survey (NERC) and th