Know all about Coal and Trachyte properties here. All properties of rocks are important as they define the type of rock and its application. Coal belongs to Sedimentary Rocks while Trachyte belongs to Igneous Rocks.Texture of Coal is Amorphous, Glassy whereas that of Trachyte is Aphanitic to Porphyritic. Coal appears Veined or Pebbled and Trachyte appears Banded. The luster of Coal is dull to vitreous to submetallic while that of Trachyte is metallic. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Trachyte is available in black, brown, dark greenish - grey, green, grey, light to dark grey, 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 Trachyte are cemetery markers, creating artwork.