Description of silicified geodes within Slunfeh formation and determination of their minerals and crystal habits

Cauliflower silicified geodes within Slunfeh Formation of upper cretaceous were described. Mid-range infrared spectroscopy FTIR was used for determination of mineral composition of these geodes. Polarized light microscope was used for the study of thin sections taken from inner parts of geodes in order to determine their crystal habits. The results showed that geodes of studied formation consists of silicon in form of amorphous to cryptocrystalline opal, chalcedony of micro-crystalline fibrous radial structure, hexagonal prismatic quartz, radial quartz, zoned quartz and mosaic quartz.