Large modern necklace. Please help to ID mark Thank you!

[rustyspoon]

Hi folks. Got this unusual sterling necklace. As much as I tried, can not decipher signature / hallmark. Can somebody please help to ID.
Thank you in advance.

[Aguest]

I can't find much information, but it could be "Sylvia Sims" if you look very close at the signature under a magnifying glass?

[Aguest]

Even though I have not seen the front of the piece, I think there are enough similarities between these two pieces to establish a relationship ___ Strange that I can't find out any information about Sylvia Sims, only that her jewelry was available at high-end luxury stores, which seems like the right place to put a piece of modernist-inspired sterling silver jewelry, you might even see an influence from the modern Scandinavian designers here, as well as the minimalist free-form sculptures of the 1970s ___ I can't explain the absence of information, it does seem peculiar, and I only found one single other piece to use as a reference (described as a "key ring") ___