I know, I'm revealing what a product whore I've truly become. I'm in an experimenting phase right now. So I'm trying liquid makeup, and I read about a facial sunscreen that supposedly plays well with liquid makeup. So I tried it. It's 6% zinc oxide and 2.5% titanium dioxide. It is invisible--and I mean invisible, not a hint of white--even when applied generously. This makes me worry that I'm not getting any sun protection, as I've never met a pure physical block without any hint of a white cast. Should I worry? Is this zinc just super micronized?