Hi guys! Just found these golden south sea pearls from Ebay (seller: echen88). The price is quite low, what do you think of these pieces? I'm new to pearls. Any advise is appreciated! Thank you so much in advance!

13mm South Sea golden pearl pendant w/chain, diamonds, solid 14k yellow gold:
https://www.ebay.com/itm/13mm-South-...cAAOSweLBaeL9V

11.2mm South Sea golden pearl earrings, diamonds, solid 18k yellow gold:
https://www.ebay.com/itm/11-2mm-Sout...MAAOSwLM5bFvCz

11.2mm golden South Sea pearl ring, diamonds, solid 18k yellow gold:
https://www.ebay.com/itm/11-2mm-gold...AAAOSwr95axAWT

11mm South Sea rich golden pearl pendant, diamonds, solid 18k yellow gold:
https://www.ebay.com/itm/11mm-South-...oAAOSwm-pZqcCC