This family was totally unknown to me. So sadly I do not know whether they still kept some of the emeralds. But after reading your post I did some "google-ing" and those emeralds are indeed huge (!) and stunning:



And on Sotheby's website there is even a photograph of the necklace worn - together with even more enormous emeralds in the tiara and "sprinkled" around the gown:

https://www.sothebys.com/en/articles/a-princely-family-with-an-astonishing-collection