And following up on the costume jewelry aspect (this is clearly costume without silver or turq), there was quite a vogue for necklaces like this one, as purely fashion. There were companies who put these out in great numbers, like Goldette, Florenza, and Art. (If you Google using the word “faux squash blossom necklace” you’ll turn up loads of examples.)
The important thing, aside from personal taste, is that no deception takes place between seller and buyer. It’s illegal for items to be sold as authentic NA goods if they are not.