[DeTomaso] Thermodynamics question

[Jerry R Knotts]

I have noticed in the last 3 radiators that I have purchased they are all 
aluminum colored.  I am currently looking at a couple of intercoolers and 
they are polished SS.  In the "old days" radiator and heater cores were 
black.  I thought that this was for additional heat conductivity.  Have the 
thermodynamic rules changed or are we accosted with "Bling".

Thanks in advance,
jerry (Wishing I was an engineer) Knotts