It's not a strap tongue, more like a brooch or perhaps a piece of furniture fitting. I would date it to the end of the 19th/beginning of the 20th century. In any case, it's something particularly beautiful!
I have a new theory. I wrote it in a comment below. What do you think?
Mirjam Scholz 6.3.2024
3 point riveted. Would be suitable for a belt tongue. But it wouldn't make sense with the enamel as the end piece of a belt that is used a lot 🤔. More like a decorative fitting on a book (book clasp part) or on leather (belt, strap etc.) I'm always cautious about the age of the enamel and would estimate it to be older than the 18th century, but that's just a gut feeling
2
SondelSuechtig 28.6.2024
I think this is a stirrup fitting. A lot comes up when you search in English. The structure is exactly the same as mine. Here is a link: Open link: www.google.com QTQtMnrHD1E_-ebSu9sbWZ5oPGpcv92PGZCTwZzUs8d8EnhRyjyhN53FgqEqsZ3PPb0KIcmz2DxVPwQLa767WNSSXjnKYgy7MLPtE56BSmFUo1IVgHa5covwg9z0eYrv8ZPFrHrlPGaNjFMrjA-8yI&sa=X&ved=2ahUKEwjEpsqFk_6GAxUDg_0HHRdkDzIQtKgLegQICRAB&biw=384&bih=700&dpr=2.81