Know all about Chalk and Variolite properties here. All properties of rocks are important as they define the type of rock and its application. Chalk belongs to Sedimentary Rocks while Variolite belongs to Igneous Rocks.Texture of Chalk is Clastic or Non-Clastic whereas that of Variolite is Glassy, Massive, Porphyritic, Scoriaceous, Vesicular. Chalk appears Soft and Variolite appears Dull and Soft. The luster of Chalk is dull while that of Variolite is not available. Chalk is available in grey, white, yellow colors whereas Variolite is available in black, brown, light to dark grey 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 Variolite are cemetery markers, creating artwork.