Know all about Tephrite and Coal properties here. All properties of rocks are important as they define the type of rock and its application. Tephrite belongs to Igneous Rocks while Coal belongs to Sedimentary Rocks.Texture of Tephrite is Aphanitic to Porphyritic whereas that of Coal is Amorphous, Glassy. Tephrite appears Vesicular and Coal appears Veined or Pebbled. The luster of Tephrite is subvitreous to dull while that of Coal is dull to vitreous to submetallic. Tephrite is available in black, brown, colourless, green, grey, white colors whereas Coal is available in black, brown, dark brown, grey, light to dark grey colors. The commercial uses of Tephrite are production of lime, soil conditioner and that of Coal are alumina refineries, electricity generation, liquid fuel, manufacture of soap, solvents, dyes, plastics and fibres, paper industry.