I've been seeing "french pearl" listings on Ebay recently and, being a veteran at this, my best guess is that it's a way of saying it's a fake (i.e. "faux") pearl.
perle
la perle
une perle
PERLE
perle
une perle (fem.)
they are famous for their black pearl
The french.
Marguerite is the French for Margaret which means "Pearl".
Nivya is supposed to mean pearl, or leader in French.
Magaly is a name of French origin, meaning "pearl".
Perle noire... No need to thank me