What diameter size are they? I agree that the shapes look like FW. The top ones looks like it has doubles, which would not be SS. Also can't see the rest of the clasp, but fish hook clasps on SS isn't the norm. The more I look at them, the more they say FW to me. I haven't handled tons of white SS but the ones I have are more of a silvery-white color. The baroque ones tend to look more like they have been poured from something liquid. I have now convinced myself that these are FW. Here's a good article with pics to help. http://www.modernjeweler.com/web/online/Pearl-Gem-Profiles/South-Sea-Baroque-Cultured-Pearls/3$261
Of course if the price is right and the pearls are super large, I've been seeing white flameball strand selling for prices that are quite high. However, I'm not sure I'd reward a dishonest person by buying from them.