Reflections will frequently be inconsistent across a surface. Wear and tear will smudge, or remove, reflection from those damaged sections of an object. With environment map reflections we have to develop strategies to simulate that variation because there is no simple command or button to do this for us. However, we can employ masks to achieve some really quite realistic results using environment maps.
You will need to extract the
faucet-blank.blend file from the
faucet-blank.zip, downloaded in the earlier recipe Creating a mesh object to provide good reflective surfaces ...