Psephite

Psephite (Greek: psephos, "pebble")^[1] 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.^[2]

Pettijohn ^[3] 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)

^ ψῆφος. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at the Perseus Project.
^ 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. 779 pp. ISBN 0-922152-76-4
^ Pettijohn F. J. (1975), Sedimentary Rocks, Harper & Row, ISBN 0-06-045191-2

[1] ψῆφος. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at the Perseus Project.

[NeuendorfOthers2005a-2] 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. 779 pp. ISBN 0-922152-76-4

[3] Pettijohn F. J. (1975), Sedimentary Rocks, Harper & Row, ISBN 0-06-045191-2

[1]

[2]

[3]