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