Kay, Raisondetre is absolutely correct.
AAA pearls come as hanks and finish up as strands after stringing, while Freshadama quality and Gem quality come from loose pearls, the ones that are usually put aside for earrings, as these pearls must be flawless as they can be seen and inspected by people.
Both Freshadama and Gem are loose, difference is just that on the gem-quality you canīt see any orient but on the Freshadama you should see at least some.
When I posted under "The one exotic" under "Show us your pearls", You can look at my Gem strand (white) together with Akoya strand (baroque), I did post it just for that reason, as so many of our members were discussing PP:s January Special, which was this strand BTW.
It is 16 inch long compared to 24 inch (Akoya-strand).
the quality then would be in PP:s case:
AA+ (never under) for Freshwater pearls:
AAA
Gem
Freshadama