Know all about Obsidian and Icelandite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian and Icelandite belong to Igneous Rocks.Texture of Obsidian is Glassy whereas that of Icelandite is Aphanitic to Porphyritic. Obsidian appears Shiny and Icelandite appears Dull and Soft. The luster of Obsidian and Icelandite is vitreous. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Icelandite is available in bluish - grey, grey, pink, yellow colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Icelandite are cemetery markers, creating artwork.