Rocks are naturally occurring solids which are composed of minerals & have been used by humans since ages. From Stone Age, rocks are used for various purposes. Also, the metals and minerals found in rock play an important role in our life. Get to know all the Phonolite Uses. We have provided you with all information about Phonolite rock here. Phonolite is an uncommon extrusive igneous rock volcanic rock of intermediate chemical composition between felsic and mafic. Phonolite is available in brown, buff, cream, green, grey, pink, white colors. The streak of a rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Phonolite is white. Get to know more about Phonolite rock and characteristics of Phonolite rock in the next sections.