The mark is a diamond shape. I can easily read Sterling and at the bottom of the diamond is 925 over 1000. But I can't read the letters at the top. The one on the left I'm pretty sure is a B tilted slight to the left (though D would be an option). At the top of the diamond, it looks like a J turned with it's top to the left. There's a mark next to it that looks like a period. But, this (along with the J-ish letter) could together be a partially imprinted S. Then there's the & sign and the last letter looks pretty solidly to be a P (though it's hard to see in the image). So, from my reading it could be BJ &P, DJ & P, BS & P or DS & P... or?
So, my questions are:
1) Is this American, and
2) Any idea of the company behind the mark and,
3) Any idea of the age (I'm thinking 1880s).
Many thanks in advance for any help. The images follow:
