Know all about Picrite and Argillite properties here. All properties of rocks are important as they define the type of rock and its application. Picrite belongs to Igneous Rocks while Argillite belongs to Sedimentary Rocks.Texture of Picrite is Earthy, Rough whereas that of Argillite is Clastic, Polished. Picrite appears Rough and Shiny and Argillite appears Rough and Dull. The luster of Picrite is subvitreous to dull while that of Argillite is waxy and dull. Picrite is available in black, brown, colourless, green, grey, pink, white, yellow colors whereas Argillite is available in dark grey to black, pink, red, white colors. The commercial uses of Picrite are as a feed additive for livestock, as armour rock for sea walls, metallurgical flux, pottery, source of magnesia (mgo) and that of Argillite are fire resistant, used to manufracture paperweights and bookends.