Antique Vintage Shell Cameo Pin Brooch Silver and Marcasite

Description

Condition as shown.  800 Silver, measures about 1 1/2" x 1 1/4"
I am not a collector, jeweler, or gemologist so my ability to answer questions is virtually zero.  I can however take additional pictures or measurements if desired. I am selling off part of my mother's collection of antique and vintage jewelry and other assorted vintage items she collected from the 1950's through her passing a few years ago.
My mother had a small summer antique shop in Maine since the 1980's, however I don't recall ever seeing any of these pieces displayed or for sale.  These items which include a wide range of gold, silver, amber, coral, and gem stone antique / vintage jewelry and everyday items were found stored in several boxes in her closet.  That said, they are clearly many of her nicest finds over 60 years of collecting.  Many will be uncommon or even one of a kind.
I will be listing many of them on eBay over time so check my other auctions.  No returns, all sales are final and items will ship insured.