help to identify origin maker of old silver platter

British Silver Reading Silver Hallmarks
1

I would like to identify the make and origin of my plate. The only thing I know is my ancestor who may have owned this was Scottish and was also a well known St.Louisian who became filthy rich trading cotton in St. Louis, Unfortunately the wealth was dwindled down to nothing so all we have is this old plate. It measures 12-3/16 in diameter. The makers marks is hard to make out although the first mark is either a bird or a clover. the second one has writing chu ?, the third is definitely a fluer de lis in within a circle. The A M in a square box underneath the marks also has me confused
any suggestions on where I can find these marks?
000_0000.JPG
000_0007.JPG
000_0001.JPG

2

Are you sure it’s silver? It looks like it could be pewter.

3

I don’t know, Does pewter have that many marks? I suppose it might be pewter

4

Yes, pewter can have lots of marks. We have had a couple of queries in these forums about items which we agreed are pewter; see for example here and here.