Does anyone know what NR engraved on the back of a necklace means?

I recently bought this delicate antique-looking gold necklace at a garage sale. It has tiny pearls inset into 5 gold filigree flowers, whose petals enclose tiny diamonds (?). Just wondering if I may have stumbled upon a real treasure.

maybe you should ask the owner or go to a jewelry store

Filigree Necklace with Swarovski @WishWare Beading Classes