color of Polycrystalline Solar panels

I just bought a 400w kit with 4 panels. The color is not consistent. One is all dark blue, one is half light blue with fractal pattern/dark blue, etc. Is this normal?

 

Im not sure if this is the norm however it is bot unheard of.
I have several shell panels which the coloring is off ( not uniform within the panel). This doesn't affect their opperation.

 

I am pretty sure it depends on the manufacturer and whether they are a,b,c graded panels.