Know all about Chalk and Phonolite properties here. All properties of rocks are important as they define the type of rock and its application. Chalk belongs to Sedimentary Rocks while Phonolite belongs to Igneous Rocks.Texture of Chalk is Clastic or Non-Clastic whereas that of Phonolite is Granular. Chalk appears Soft and Phonolite appears Banded and Foilated. The luster of Chalk is dull while that of Phonolite is greasy to dull. Chalk is available in grey, white, yellow colors whereas Phonolite is available in brown, buff, cream, green, grey, pink, white colors. The commercial uses of Chalk are alumina refineries, creating artwork, drawing on blackboards, gymnasts, athletes and mountain climbers use for grip, in aquifers, paper industry, production of lime, raw material for manufacture of quicklime, slaked lime, soil conditioner, whiting, whiting material in toothpaste, paint and paper and that of Phonolite are cemetery markers, creating artwork.