1) Sedimentary rock 
Psephite (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 ru...
psephite, psephitic A conglomerate composed of pebbles or small rounded stones.
any coarse rock, as breccia or conglomerate.