Know all about Rapakivi Granite and Obsidian properties here. All properties of rocks are important as they define the type of rock and its application. Rapakivi Granite and Obsidian belong to Igneous Rocks.Texture of Rapakivi Granite is Granular, Phaneritic whereas that of Obsidian is Glassy. Rapakivi Granite appears Veined or Pebbled and Obsidian appears Shiny. The luster of Rapakivi Granite is dull to grainy with sporadic parts pearly and vitreous while that of Obsidian is vitreous. Rapakivi Granite is available in black, grey, orange, pink, white colors whereas Obsidian is available in black, blue, brown, green, orange, red, tan, yellow colors. The commercial uses of Rapakivi Granite are cemetery markers, commemorative tablets, creating artwork, curling, laboratory bench tops, tombstones and that of Obsidian are creating artwork, mirror, used in aquariums.