Please help with this unusual hallmark!!!

Hi, Can you please help me identify the hallmarks on this butter knife? I’ve spent hours looking on the internet and can’t find anything similiar, it’s the circle that’s thrown me!? Could you possibly tell me the date & where it was made and if it’s silver? Many thanks :smiley:
002 (5).JPG
015 (2).JPG

Not a silver hallmark, I am sorry to say. It is a silver plate mark of Daniel & Arter c1880.

Thankyou for your response, case solved! :smiley: