Please note that the schools of literary criticism and their explanations included here are by no means the only ways of distinguishing these separate areas of theory. Indeed, many critics use tools from two or more schools in their work.
Conglomerate is a clastic sedimentary rock that contains large (greater than two millimeters in diameter) rounded clasts.
Clastic Sedimentary Rocks are those that are composed of fragments of other rocks (igneous, metamorphic, sedimentary). Depending on grain size they are subdivided into conglomerate (grain size larger than 2 mm), sandstone (size between 2 mm and 0.0625 mm), and shale (mudstone).