This is an enhancer with the odd hallmark. Wondering if you have any thoughts about the hallmark and also the enhancer itself, which is an unusual shape.
When you first wrote using the word “enhancer” I had no idea what you meant. After doing a bit of looking, it seems to me that an enhancer is a cousin to a pendant in that it is used with a necklace of some sort. In the case of yours, the enhancer has a Shepherds Hook which will allow the piece to be hooked in between silver or stone beads as well as on a sterling silver collar and more. Other enhancers have hinged hooks so that you can open and clip the enhancer onto a necklace and click it securely closed.
Whereas a pendant usually has a swinging or fixed bail or loop on the back through which the necklace is strung. Some Native American pendants or pin-pendants have Shepherds Hooks.
So now that we have that out of the way, for my benefit and that of other readers, not yours, since you already know that ! On to the piece.
I am immediately drawn to the hand cut and decorated bezel which is really special.
I keep looking at its overall composition and shape and something seems very familiar to me yet I can’t remember where I have seen this shape. It seems to have a religious significance in my brain. Now that I have seen it, I will keep my eyes open. I have a huge reference library here and often when paging through one of my books, looking for one thing, I’ll spot something else. So I have this on the “back burner”.
I’m sorry I can’t be of help with the hallmark – it just doesn’t look familiar to me.
However by posting the photos, perhaps we will find someone who knows about this piece and its maker.
Thanks for writing and happy holidays !