Clasts are smooth to touch, Is one of the oldest rock, Smooth to touch, Very fine grained rock
Flint, Jasper, Radiolarite, Common Chert, Chalcedony, Agate, Onyx, Opal, Magadi-type Chert, Porcelanite, Siliceous Sinter
Clasts are smooth to touch, Easily splits into thin plates, Has High structural resistance against erosion and climate