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