| Outstanding feature | Chert replaces bioclastic grains & micrite          and spar cement | 
             | Folk Classification | Chertified foraminifera biomicrite | 
             | Dunham Classification | Chertified foraminifera packstone | 
             | Common Grains | Foraminifera, intraclasts & micrite envelopes | 
             | Sorting | Well sorted | 
             | Rounding | Well rounded | 
             | Micritization &          envelopes | Micrite envelopes common | 
             | Cement & diagenetic          fabric | Almost complete replacement by chert | 
             | Porosity | No porosity | 
             | Depositional          Setting | High energy shoal | 
             | Diagenetic          history | Chertification of skeleletal          grains and micrite cement | 
   
   Replacement of skeletal and micritic      materials by chert.