Know all about Coal and Diorite properties here. All properties of rocks are important as they define the type of rock and its application. Coal belongs to Sedimentary Rocks while Diorite belongs to Igneous Rocks.Texture of Coal is Amorphous, Glassy whereas that of Diorite is Phaneritic. Coal appears Veined or Pebbled and Diorite appears Shiny. The luster of Coal is dull to vitreous to submetallic while that of Diorite is shiny. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Diorite is available in black, brown, 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 Diorite are creating artwork, curling.