Know all about Gritstone and Tephrite properties here. All properties of rocks are important as they define the type of rock and its application. Gritstone belongs to Sedimentary Rocks while Tephrite belongs to Igneous Rocks.Texture of Gritstone is Earthy whereas that of Tephrite is Aphanitic to Porphyritic. Gritstone appears Layered and Foliated and Tephrite appears Vesicular. The luster of Gritstone is dull while that of Tephrite is subvitreous to dull. Gritstone and Tephrite are available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. The commercial uses of Gritstone and Tephrite are an oil and gas reservoir, as a feed additive for livestock, gemstone, metallurgical flux, production of lime, soil conditioner, source of magnesia (mgo), tombstones.