Thank you for contacting Mearto with your appraisal inquiry.

It is a beautiful pearl and jade necklace. Such vintage jewellery are being offered at auction on a regular basis.
The jade has a lovely colour, however it is hard to tell whether it is pressed jade or cut jade. The lock may be silver - I cannot see any marks on the photos you have sent. It is a lovely necklace with a classic design that would attract the attention of both collectors and dealers if it came up for auction.
The estimate provided is for a well-advertised specialised online jewellery auction, where I believe the necklace has the best chance of realising its fullest potential. However, there is no measurement for the sentimental value you might attach to the jade and pearl necklace. Retail "asking prices" can be higher and vary.

Please let me know if you have any additional questions. I’m happy to help.
Thank you