Psephite
Psephite is either a sediment or sedimentary rock composed of fragments that are coarser than sand and which are enclosed in a matrix that varies in kind and amount. It is equivalent to a rudite. Shingle, gravel, breccia, and especially conglomerate, would all be considered psephites. It is equivalent to the Latin-derived term rudite. Psephite is more commonly used for a metamorphosed rudite.
Pettijohn gives the following descriptive terms based on grain size, avoiding the use of terms such as "clay" or "argillaceous", which carry an implication of chemical composition:
| Texture | Common | Greek | Latin |
| Coarse | gravel | psephite | rudite ' |
| Medium | sand | psammite ' | arenite ' |
| Fine | clay | pelite ' | lutite |