Did you closely check the back and clasp for any marks or stamps? For a piece as elaborate as that (stunning by the way), I would have thought there would be a maker's mark.
Does your wife remember when and how it came into her possession -- whether she bought it new herself or received it as a gift, the year would be helpful. If it is a family piece, the origin story would be helpful.
Is that your photo by the way? It looks to me more like vendor photo.
Welcome!
Looks like it was on eBay -- that's an eBay photo or screen grab but the text is just a category name.
The metal-work looks wavy to my eye -- between the rows of the largest sections in the front. I would not expect that. Could just be an artifact in the photo but it's possible that it's not genuine. Also, there is a huge excess of metal, to my eye, and that typically would not be the case with gold. I may be 100% wrong but it raises my suspicion for plated base metal.
Thank you, hopefully you are wrong but one never knows.