Which colors are translucent

[tyler07]

...okay, so the last two bodies i've painted i used three light coats of metallic burgundy (rattle can) and then a coat of black underneath. The resulting color is a really cool deep purple that i like a lot. So i figured i'd do the same with a blue car. I used metallic blue in the same amount, but when i backed it with black, it didnt change color at all, and now i can see a few light spots where the black is showing through a little. I'll still finish the car, but instead of a real dark blue, i've got a blue color that i've seen a thousand times before at my track.

So here's my question: Are some metallic colors transparent and some not?...are all candy colors transparent?...should i have used candy blue instead of metallic blue?

thanks!:D