Don`t forget that the adept/mentee or coachee is the most important here. The result is far more important than if he has a coach or a mentor. I know this is fuel to the fire but I dare.
We can also be a bit simple in the explanation and say that as a mentor you see it as the responsibility to offer appropriate support, suggestions based on your professional knowledge and even introductions to the adept/mentee.
As a coach you work with the coachee for them to discover their own paths – and to decide what they want to do and who they might ask to be part of their plan.