Thank you for contacting Mearto with your appraisal inquiry.

It is a beautiful necklace with pendant.
The Danish designer and poet Piet Hein created the super ellipse shape in 1959. It was made both in silver, steel and brass and the shape was used for many things apart from a necklace pendant. The pendant is rarely seen and I believe it was made by Georg Jensen silver. However in order to determine the silver and maker I would need to see a photo of the marks which are possibly stamped on the chain and on the pendants eyelet.

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