Featured CCORI brooch - 22k plated?

Hi, everybody! I have this brooch by CCORI that I’m in the process of listing for sale, and when I did a little research to find a suitable price, I kept seeing that everyone else lists it as being 22k plated. It looks like gold, so I totally believe that it is plated, but I can’t find any marks on the piece to confirm that. And other CCORI pieces - earrings, necklaces, etc. - are also listed as 22k plated. Is it possible that all of their jewelry is plated but unmarked?
Thanks!

 

Looks like there could be 2 marks.

Made in Peru,they probably are not required to mark for gold plating.

 

They are by the firm CCori, a firm that made jewelry based on ancient pre-Columbian motifs from South and Central America. According to information on the web, CCori supplied jewelry to museum shops and also to Neiman Marcus in the 1980s.

 

Love the brooch, TanyaG. Gold plated base metal is not marked in many countries, including Peru.

This necklace has the same design as a pendant:
https://www.rubylane.com/item/470807-RFWB32208/Vintage-Neiman-Marcus-Gold-Plate-Necklace

According to the seller it is an 1980s design made exclusively for Neiman Marcus.
They say: "It is not a replica but an inspiration piece." Meaning it was inspired by pre-Columbian art.

 

Thanks, everybody! You are appreciated…