So I tried to search around to find an answer to this, but I'm still puzzled. I understand that most automotive greases use lithium as a thickener (i.e. the soap which keeps whatever oil the grease has as its base). From what I can gather, the only difference with 'WHITE lithium grease' is that it has zinc-oxide added to it - but why? I've seen a few sources say that it's just for seeing where the grease got applied or whether it's contaminated (so purely visual benefits). Is this true? When would you use white lithium grease over something else?