Know all about Obsidian and Theralite properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian and Theralite belong to Igneous Rocks.Texture of Obsidian is Glassy whereas that of Theralite is Phaneritic. Obsidian appears Shiny and Theralite appears Veined and Shiny. The luster of Obsidian is vitreous while that of Theralite is waxy and dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Theralite is available in dark grey to black colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Theralite are cemetery markers, commemorative tablets, creating artwork, laboratory bench tops, jewelry, sea defence, tombstones.