Know all about Coal and Siltstone properties here. All properties of rocks are important as they define the type of rock and its application. Coal and Siltstone belong to Sedimentary Rocks.Texture of Coal is Amorphous, Glassy whereas that of Siltstone is Clastic. Coal appears Veined or Pebbled and Siltstone appears Rough. The luster of Coal is dull to vitreous to submetallic while that of Siltstone is dull. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Siltstone is available in brown, red, reddish brown 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 Siltstone are raw material for the manufacture of mortar, soil conditioner.