Is this a Kathy Yazzi piece or not please help!!!

The cross was ver dirty when I found it cleaned it as best as I could myself so it did have a lot of age to it also the KY stamp matches my research but the way the sterling is is different the boom I read showed sterling In almost italic print mines not but if anyone can authentic it please do so!!! Also I’m curious if the turquoise is real??? It’s not plastic resin because I used the hot needle test and it never burnt but my main concern is if it’s Kathy Yazzi I’ve seen 1or 2 others only claim there’s as Yazzi and asking a lot for them I don’t want to sell I just want to authentic it and store it proper if it’s real. The boom I was looking in showed same stamps for her except in the book the sterling was almost and italic fo t as mine is regular font but other pieces online are the same and claim to be Yazzi I just want a 100% positive answer the bad polishing I did (sorry) I also added the necklace to it I just need cross identification and authenticated I added plenty of images I hope if any other pictures are needed to authentic just ask! Thank you all so much!!!