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