Know all about Blue Granite and Obsidian properties here. All properties of rocks are important as they define the type of rock and its application. Blue Granite and Obsidian belong to Igneous Rocks.Texture of Blue Granite is Phaneritic whereas that of Obsidian is Glassy. Blue Granite appears Shiny and Obsidian appears Shiny. The luster of Blue Granite is subvitreous to dull while that of Obsidian is vitreous. Blue Granite is available in black, brown, light to dark grey, white colors whereas Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. The commercial uses of Blue Granite are cemetery markers, commemorative tablets, creating artwork, curling and that of Obsidian are creating artwork, mirror, used in aquariums.