faint blue swirl in oil

This is my first oil change since dumping mobil 1 semi-synth in the car. When I looked at my old oil in the container I noticed a very faint blue hazy swirl type of stuff in it. I could only see it in the oil if I got directly into sunlight and looked right into it. I've never seen such a thing in my old dino oil?? Is this normal semi-synth? BTW I have no experience with semi-synth or synth. There shouldn't have been any moisture in the container before the oil change.. might have been dried up simple green though. The blue stuff isn't rainbowish. I have dumped engine restore in my oil before and it is blue.. is it possibly the mobil 1 cleaned up some of it? I'm just worried that it might be coolant or something... i'm always paranoid and silly about head gasket probs. Any ideas?

Bad Juju.
You have offended the Volvo gods.
Sacrifice a Honda cold-air filter, quick.

I don't think it's anything wrong.

I think i've figured out what it was. Week or 2 before my change to mobil 1 semi-synth I had dumped a can of engine restore in the car. Engine restore is blue so I am betting thats engine restore gunk i'm looking at. It would be more visible because semi-synth is not as dark as dino. Just my guess.