Know all about Siltstone and Anthracite properties here. All properties of rocks are important as they define the type of rock and its application. Siltstone belongs to Sedimentary Rocks while Anthracite belongs to Metamorphic Rocks.Texture of Siltstone is Clastic whereas that of Anthracite is Amorphous, Glassy. Siltstone appears Rough and Anthracite appears Veined or Pebbled. The luster of Siltstone is dull while that of Anthracite is shiny. Siltstone is available in brown, red, reddish brown colors whereas Anthracite is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Siltstone are raw material for the manufacture of mortar, soil conditioner and that of Anthracite are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry.