Great Tutorial! Mixing Materials is really fun and i love how u pay close attention to all the details and relate it to the real world.
Anyways are there more tutorials in which the nodes get explained? For example the "Texture coordinate node" and the "math node". I understand why u add them and how they influence our texture, but still i wanna know how they operate.
Mixing materials is definitely awesome! If you're interested in learning more, I'd recommend watching our Shader Forge course which goes more in-depth: https://cgcookie.com/course/shader-forge