Know all about Obsidian and Porphyry properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian and Porphyry belong to Igneous Rocks.Texture of Obsidian is Glassy whereas that of Porphyry is Porphyritic. Obsidian appears Shiny and Porphyry appears Dull. The luster of Obsidian is vitreous while that of Porphyry is dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Porphyry is available in black, brown, colourless, green, grey, red, rust, white colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Porphyry are creating artwork, gemstone, jewelry.