argillite
NounWordNet 3.0
Noun (1)
- a sedimentary rock differing from shale in being bound by silica and from slate in having no slate cleavages
Webster's Dictionary (GCIDE)
Argillite \Ar"gil*lite\, n. [Gr. ? clay + -lite.] (Min.) Argillaceous schist or slate; clay slate. Its colors is bluish or blackish gray, sometimes greenish gray, brownish red, etc. -- Ar`gil*lit"ic, a. [1913 Webster]