Know all about Blue Granite and Siltstone properties here. All properties of rocks are important as they define the type of rock and its application. Blue Granite belongs to Igneous Rocks while Siltstone belongs to Sedimentary Rocks.Texture of Blue Granite is Phaneritic whereas that of Siltstone is Clastic. Blue Granite appears Shiny and Siltstone appears Rough. The luster of Blue Granite is subvitreous to dull while that of Siltstone is dull. Blue Granite is available in black, brown, light to dark grey, white colors whereas Siltstone is available in brown, red, reddish brown colors. The commercial uses of Blue Granite are cemetery markers, commemorative tablets, creating artwork, curling and that of Siltstone are raw material for the manufacture of mortar, soil conditioner.