AF or AE within Crown?

Hi,
This is only a tiny spoon (10cm) that I picked up in a small lot of mostly plate, and I was mainly after this to use as a salt spoon. However, I can’t seem to find any silversmith hallmarks similar to this.I am pretty sure that it is London, and the date letter is a B … I apologise for the pictures, the marks are quite rubbed, but if anyone can help that would be great!

Thanks

Mario
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I haven’t been able to identify this, but I’m sure it’s an electroplate mark. I suspect that the lettering in the crown is most likely A1 - the plating grade mark. It is certainly not a London hallmark.