London silver, but from what year

Hi everyone,
My eyes are not what they once were, and my photography skills are probably not much better, but I believe I’ve got a London hallmark and the year seems to me to be either 1849, 1851, or 1855. Can anyone take a look and compare to the London date chart and help me out?

That’s the 1851 Q.


Thanks Phil. I’m sorry I didn’t respond until now. Somehow I missed it.
I’m not sure why I said London as now I can’t make heads or tails of the other symbol aside from the Q you identified as an 1851 Q. Are the years also distinct by City and is that how you confirmed it’s London? Can you tell me what the second stamped mark is?
Thanks again,