Know all about Porphyry and Chalk properties here. All properties of rocks are important as they define the type of rock and its application. Porphyry belongs to Igneous Rocks while Chalk belongs to Sedimentary Rocks.Texture of Porphyry is Porphyritic whereas that of Chalk is Clastic or Non-Clastic. Porphyry appears Dull and Chalk appears Soft. The luster of Porphyry and Chalk is dull. Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors whereas Chalk is available in grey, white, yellow colors. The commercial uses of Porphyry are creating artwork, gemstone, jewelry and that 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.