Know all about Pseudotachylite and Argillite properties here. All properties of rocks are important as they define the type of rock and its application. Pseudotachylite belongs to Metamorphic Rocks while Argillite belongs to Sedimentary Rocks.Texture of Pseudotachylite is Quench whereas that of Argillite is Clastic, Polished. Pseudotachylite appears Dull and Soft and Argillite appears Rough and Dull. The luster of Pseudotachylite is vitreous while that of Argillite is waxy and dull. Pseudotachylite is available in black, brown, colourless, green, grey, pink, white colors whereas Argillite is available in dark grey to black, pink, red, white colors. The commercial uses of Pseudotachylite are creating artwork, gemstone and that of Argillite are fire resistant, used to manufracture paperweights and bookends.