The occurrence of crandallite in a sinkhole near Florze (Belgian Condroz)

Abstract

Crandallite has been found in a sinkhole near Florzé where recently also halloysite was discovered. The mineral occurs in a pocket in a residual clay derived from Visean limestones. The clay is found on top of Om and Onx deposits and below Pleistocene solifluction material. X-ray diffraction patterns, D.T.A.-traces, specific density separation, refractive indexes, X-ray fluorescence patterns and chemical composition have been determined and are reported. The samples are rich in uranium.