Psammite (Greek: psammitēs "(made) from sand", from psammos "sand")[1] is a general term for sandstone. It is equivalent to the Latin-derived term arenite[2] [3] and is commonly used in various publications to describe a metamorphosed sedimentary rock with a dominantly sandstone protolith.[4] In Europe, this term was formerly used for a fine-grained, fissile, clayey sandstone.[3] Pettijohn[5] 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(ly) | psephite (psephitic) | rudite (rudaceous) | |
| Medium | sand(y) | psammite (psammitic) | arenite (arenaceous) | |
| Fine | clay(ey) | pelite (pelitic) | lutite (lutaceous) |