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