| Abstract: | An unusual nodular form of monazite has been found to account for abnormally high levels of cerium in panned heavy mineral concentrates from stream sediments in several areas in Wales and pan of Exmoor. Textural features indicate a pre-metamorphic, diagenetic origin within Lower Palaeozoic shale or siltstone host-rocks but REE patterns show only minor variation, including relative enrichment in europium, from ‘average’ granitic monazite. The similarities between these occurrences, described for the first time from the British Isles, and those previously described from Brittany and elsewhere are discussed. |
