We call it Gold Fever. It's when you've got a hankerin to have a nice flat surface to put that BGA on and the lust for that precious metallic surface turns into an obsession. It's all you can think of. You forsake your family, your job and even your level 68 Night Elf druid for but a glimpse of that resident of period 6, group 11. Ahhh, yes (or Auuu, yes), the all desired number 79...
Okay, maybe we don't call it "gold fever", but it certainly can cause you a fever in your time line and budget if your gold board comes back with spots like this one did. In addition to the obvious four spots with visibly degraded Au layer, this whole set of PCBs probably has black-pad written all over it. If you have other boards that came from the same batch as one like this, you should give them a very close examination. At least make sure you've got a good healer class in your guild.
In case you haven't been caught by the scourge of black pad, just know that the Argent Dawn can't help you here. Black pad is caused (and I'm generalizing, not going into exact technical details) when there's a little contamination in the nickle layer of an ENIG (Electroless Nickle Immersion Gold) pcb during fab.
When the component is then soldered on, the solder mixes with the gold but not the underlying nickel layer and the part can later pop off or at least not conduct your signals or complete your quests. It's most commonly associated with BGAs, but can occur with other types of components too.
It's safe back here in Goldshire, but all I can find is copper.