Hiya,
Does anyone recognise this shape of hallmark or where it may be from? I love this brooch and it looks old.
Thanks everyone! 
I just can’t make out that lozenge-shaped mark to tell which country it is, though to me it looks most like it’s French. You might look up French silver marks and see if one of them matches what you have there. Or, if you’re able to take a clearer picture of the mark. It looks a bit like one from 1819-1838.
Hiya,
Thanks so much for your thoughts, I really appreciate that, I thought it seemed old.
Best wishes
You’re welcome, good luck in your search for more information.