Know all about Diorite and Coal properties here. All properties of rocks are important as they define the type of rock and its application. Diorite belongs to Igneous Rocks while Coal belongs to Sedimentary Rocks.Texture of Diorite is Phaneritic whereas that of Coal is Amorphous, Glassy. Diorite appears Shiny and Coal appears Veined or Pebbled. The luster of Diorite is shiny while that of Coal is dull to vitreous to submetallic. Diorite is available in black, brown, light to dark grey, white colors whereas Coal is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Diorite are creating artwork, curling and that of Coal are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry.