Characteristics related to grain size of rocks are called as texture. Here you can know more about texture of Rapakivi Granite and Obsidian. Texture of Rapakivi Granite is Granular, Phaneritic whereas that of Obsidian is Glassy. Based on the texture of rocks, they are used for various purposes. Get detailed information about Rapakivi Granite vs Obsidian texture, color, appearance and maintenance in the next section.