tungsten questions for aluminum

[nanaf]

I've seen a blue tungsten for myself once. I don't remember what I thought the reason for it occurring was but I was very intrigued.
I was going to make a thread asking this question but I saw this thread and figured this would do. What tungsten is 'best' for AC aluminum? I have zirconiated, which is what I use on AC transformer machines, but I haven't tried it yet. I have tried thoriated and it seems to work ok. Although, the tungstens tip ends up looking a bit odd, but I am likely putting too many amps into a 1/16ths tungsten, around 110.

Sometimes I have read bits about ceriated being better, and sometimes I have read bits about 2% lanthanated being better.

[Wrenchtamer]

blue tungsten is oxidation due to inadequate post flow. kick up the post flow a little. by the way, I stepped up to a 5/32 2% thoriated and was fially able to weld my guitarist's ladder jack back tgether. corner joint 1/4 architectural angle. w/ no preheat. I love this freaking machine.

[performance]

Nanaf,
110 A is way too much especially in an inverter on this size electrode.