ABSTRACT
In the Gedaref region of NE-Sudan, sedimentary kaolins with flint-clay character are widely distributed. The kaolinitic rocks, which are most likely of Cretaceous age, have been affected by secondary silicification (opaline silica) and alunitization. According to the geological situation, both hypogene (hydrothermal activity) and supergene (weathering) processes could have been responsible for this type of alteration. Practical utilization of the huge reserves of kaolins seems to be limited.
