Know all about Argillite and Rapakivi Granite properties here. All properties of rocks are important as they define the type of rock and its application. Argillite belongs to Sedimentary Rocks while Rapakivi Granite belongs to Igneous Rocks.Texture of Argillite is Clastic, Polished whereas that of Rapakivi Granite is Granular, Phaneritic. Argillite appears Rough and Dull and Rapakivi Granite appears Veined or Pebbled. The luster of Argillite is waxy and dull while that of Rapakivi Granite is dull to grainy with sporadic parts pearly and vitreous. Argillite is available in dark grey to black, pink, red, white colors whereas Rapakivi Granite is available in black, grey, orange, pink, white colors. The commercial uses of Argillite are fire resistant, used to manufracture paperweights and bookends and that of Rapakivi Granite are cemetery markers, commemorative tablets, creating artwork, curling, laboratory bench tops, tombstones.