50F. I know this only because I am an American in Wales, and that is one of the few that I can remember because they are both round numbers.
I thought you were referring to a bra size.
I realize that this is a thread for “nipples” not areolas so i am gunna get back on track and i’m gunna say that my mother has well very large nipples maybe the size of gumdrops, perhaps bigger. The thing is, they are always like that, me on the other hand (15) Have very small ones, about the size of a small pea
actually it sn’t about nipples at all. 1. I didn’t think larger Areolaed women had the same ring 
and 2. I thought not mny people would know what I was talking about.
Just in case this is not a joke, think of it this way:
If the nipple is Orthanc, the areola is Isengard.
Pictures here.
nipples are the bumps and the areola are the darker skin surrounding the nipples, the nipples can be appart of the areola, they are in the center of them.