Don't put light on tile. It is a glossy thing(like a car). First rule in lightning glossy material is make the environment look good in reflections.
Example of shooting and lighting a car(or any glossy surface):
When you watch cars shapes, you see reflections of environment around you. If you put light straight to the car it is really putting a light straight to to cameras lens and that burns immediatly(like a mirror). If you put white fabric or some big thing and put light pointing there you can play how white that looks like in cars reflection and how the gradation goes...
Hope that helps you
