Psammite (Greek: psammos, "sand") is a general term for sandstone. It is equivalent to the Latin-derived term arenite[1][2] and is commonly used in various publications to describe a metamorphosed sedimentary rock with a dominantly sandstone protolith.[3] In Europe, this term was formerly used for a fine-grained, fissile, clayey sandstone.[2] Pettijohn [4] 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)


  1. ^ U.S. Bureau of Mines Staff (1996) Dictionary of Mining, Mineral, & Related Terms. Report SP-96-1, U.S. Department of Interior, U.S. Bureau of Mines, Washington, D.C.
  2. ^ a b Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, J.A., eds. (2005) Glossary of Geology (5th ed.). Alexandria, Virginia, American Geological Institute, Washington, DC 779 pp.
  3. ^ Tyrell, G. W. (1921) Some points in petrographic nomenclature. Geological Magazine. v. 58, no. 11, pp. 494–502.
  4. ^ Pettijohn F. J. (1975), Sedimentary Rocks, Harper & Row, ISBN 0-06-045191-2