Completely mysterious (to me) hallmark

I am not even sure if this is sterling or plated since I can’t make heads or tails of the hallmark. It is on the back of a footed large grape pattern tray. It looks like a right facing sea monster on the left, a crescent in the center and a left facing bird or phoenix head on the right. It is engraved “Crescent” with the number 1099F underneath. I would love to know what in the world I have: country, maker, date, is it sterling or plate? Thanks to anyone who can help me. Excuse the photo of my foot, I was trying to give the scale of the piece.
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That is an American set of silverplate marks.
Check out the Crescent Silverware Manufacturing Company here:
925-1000.com/silverplate_C.html