Know all about Obsidian and Phonolite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian and Phonolite belong to Igneous Rocks.Texture of Obsidian is Glassy whereas that of Phonolite is Granular. Obsidian appears Shiny and Phonolite appears Banded and Foilated. The luster of Obsidian is vitreous while that of Phonolite is greasy to dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Phonolite is available in brown, buff, cream, green, grey, pink, white colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Phonolite are cemetery markers, creating artwork.