Know all about Coal and Rhyolite properties here. All properties of rocks are important as they define the type of rock and its application. Coal belongs to Sedimentary Rocks while Rhyolite belongs to Igneous Rocks.Texture of Coal is Amorphous, Glassy whereas that of Rhyolite is Aphanitic, Glassy, Porphyritic. Coal appears Veined or Pebbled and Rhyolite appears Banded. The luster of Coal is dull to vitreous to submetallic while that of Rhyolite is earthy. Coal is available in black, brown, dark brown, grey, light to dark grey colors whereas Rhyolite is available in grey, white, light black 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 Rhyolite are gemstone, laboratory bench tops, jewelry.