The metalness
Metalness is one my favorite tools for designing an object. It is like a magic!
Whenever you want to show the client a really deep and close view to the object you have to use metalness method.
Higher amount of metalness will create a shinier surface but the penalty of using this method is putting CPU on the high pressure calculations . So basically if you use this Technic so much you will have a lot of lags 🙂