Procedural mesh color vs built-in primitive colors?

Good day
I needed a ring shaped object in my project. I managed to create a ring shaped mesh dynamically through script and I can implement it in my project.
However the color difference between the ring mesh and the built-in primitives (e.g. cylinder) just baffles me a bit.
I have uploaded a screen shot of what I mean. The ring mesh appears very white and the primitive cylinder (created from the list of 3D Objects n Unity) much more grey. I have added exactly the same standard shader to both of them.
This is annoying because in my project I add cylinders to the ring mesh and they need to be the same color as the ring mesh. See picture 2: The darker green circles should be the same color as the light green ring. Preferably I would like to have my ring mesh appear the same as the shading of the primitives.
What am I missing here?
Kind regards.

 

Probably the normals are wrong.

--Eric

 

Hi Eric
Yes, thanks. That was the problem. The normals pointed in the wrong direction.
Regards.
Kobus