Unusual British hallmark identification please

I brought 2 ivory forks with 3 marks.
Have no idea what the first stamp is ???
2nd stamp I believe is George III
3rd stamp is the Lion passant

Please help with town / date / maker ???


This is a Sheffield hallmark for the assay year 1815/16. The crown town mark and date letter “O” are combined in this form of the hallmark which was used on smaller items of silver.

Phil