Sewnoma

It could be windblown but it looks like standard soap ash to me - if that's not what it is on this batch, you'll get it sooner or later!

But don't worry, it's not a problem at all and nothing went wrong, it's just a by product of the saponification process; you see it more commonly when the soap didn't go through gel phase - gel phase is when the soap mix continues a chemical reaction and gets hot after going through trace; it changes the texture of the soap and it will temporarily appear be a translucent gel while it's happening - hence the name. Some people like it because the soap generally cures faster and (sometimes) results in a harder soap bar; some people hate it and deliberately chill the soap to avoid it because it tends to 'burn off' a lot of fragrance and they don't like the harder texture. Uneven gel can happen too, where the center of the mold goes into gel but the rest doesn't, which gives you some bars that are half-and-half. It's harmless as far as function goes; the soap works just as well, but it can look and feel a little different.

That's why I always forced gel phase with the whole warm oven routine; guaranteed consistency from batch to batch. Important for sales...not nearly as critical for hobby.