Know all about Coal and Argillite properties here. All properties of rocks are important as they define the type of rock and its application. Coal and Argillite belong to Sedimentary Rocks.Texture of Coal is Amorphous, Glassy whereas that of Argillite is Clastic, Polished. Coal appears Veined or Pebbled and Argillite appears Rough and Dull. The luster of Coal is dull to vitreous to submetallic while that of Argillite is waxy and dull. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Argillite is available in dark grey to black, pink, red, white colors. The commercial uses of Coal are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry and that of Argillite are fire resistant, used to manufracture paperweights and bookends.