Mesh Intersection Detail (Line,Points)

I know I can easily respond to when a mesh intersects another collider. However, I have a box collider and when the mesh intersects I'm trying to figure out the dominate color of the mesh that falls within the collider. Is this possible?

If my mesh consists of vertex colors and not textures I would imagine going through all polys that intersect the collider and then figuring out the vertex colors of all points that make up the polys. Then doing some averaging...

Is all of this possible in the unity engine w/c# scripting? I'm not sure what methods I would have access to in order to achieve this goal..

Any help would be appreciated!

-jv