Thank you for contacting Mearto with your appraisal inquiry.

It is a beautiful necklace set with an opal. Such vintage jewellery are being offered at auction on a regular basis.
This is the type of jewellery that never goes out of fashion and may be worn both at daytime and in the evening. The design is very nice and elegant. The colour of the opal is good and the 14kt yellow gold matches the stone very well.
As this is a design that has been popular for many years it is hard to say exactly when it was made however I would suggest that is dates from the last half of the 20th century.

The estimate provided is for a well-advertised specialised online jewellery auction, where I believe the necklace with pendant has the best chance of realising its fullest potential. However, there is no measurement for the sentimental value you might attach to the opal pendant. 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