Know all about Obsidian and Oil shale properties here. All properties of rocks are important as they define the type of rock and its application. Obsidian belongs to Igneous Rocks while Oil shale belongs to Sedimentary Rocks.Texture of Obsidian is Glassy whereas that of Oil shale is Splintery. Obsidian appears Shiny and Oil shale appears Muddy. The luster of Obsidian is vitreous while that of Oil shale is dull. Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors whereas Oil shale is available in black, brown, buff, green, grey, red, yellow colors. The commercial uses of Obsidian are creating artwork, mirror, used in aquariums and that of Oil shale are an oil and gas reservoir.