How blue is 100LL?

I usually pump my own, but today I called ahead and had the FBO fill it
for me (only 53 cents more/gal!). I wasn't even present for the fueling
so I was extra paranoid during preflight, and I swear the 100LL was not
as "blue" as it usually is. It smelled like gas, and when I finally got
a big enough sample you could see a slight blue tint, but on a dip tube
I would have sworn it was clear.

So how blue is it supposed to be? Is there another simple test I could
have done to reassure myself (besides burning 30gal of it and having it
work fine)?

--
Ben Jackson

http://www.ben.com/