Antique Silver Tone Marcasite? Double Locket Mourning Brooch

Description

First I want to tell you where I bought the locket.
I bought a lot at an estate jewelry auction labeled "mourning jewelry".
Whether this is a mourning locket or not...I do not know.
The woman who it belonged to died last year at the age of 99.
She had collected jewelry her whole life and there were so many pieces that it took four separate large auctions for it all.
I was lucky enough to get a few lots...this being one piece of one.
So ok...I do not know what the metal is, but a magnet is not attracted to it
It has a very intricate design with marcasite stones entwined
Many of the tiny marcasite stones are missing
It is a double locket brooch and opens on both sides
Opens and closes easily
It measures 2" wide x 1" high
Clasp is in good working condition
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