title: Psephite
text: # Psephite
  
  Psephite (Greek: psephos, "pebble") 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:
  
  Descriptive size terms :
  
  | Texture | Common | Greek | Latin |
  | - | - | - | - |
  | Coarse | gravel(ly) | psephite (psephitic) | rudite (rudaceous) |
  | Medium | sand(y) | psammite (psammitic) | arenite (arenaceous) |
  | Fine | clay(ey) | pelite (pelitic) | lutite (lutaceous) |
  