Help with American coin silver maker identification

[oldcheesenips]

Hello,

I picked up several coin silver spoons at an estate sale.    I’ve been able to identify most of them as coming from Norfolk or Philadelphia, but I can’t identify this little guy.

The maker mark  is R & Potter.   The spoons are about 5 inches long, very thin and very well used with signs of abuse.  No monogram.

another group of spoons seems to be silver but I can read anything but the word Standard.  There is something written to the left of that word.  These spoons are flexible and quickly warm up in hot water.  Any help is appreciated.

many thanks for your help!

[fidbald]

the top one. was it tested for silver ? looks like tin lead alloy that was used for jail flatware. not dangerous in fights and attacks and not useful as tool for jailbreak.

[oldcheesenips]

Thanks for your response.     I haven’t any way of testing it for silver.   I did use some silver cleaner on it and the cloth came up black as coal.  I also put it in some warm water and it conducted heat quickly.   So I think I the spoons are probably  silver but of marginal quality as they are so thin and so well used.   And definitely ineffective for a weapon or jailbreak.    
I’m just curious as to the maker and the time frame if anyone would hazard a guess.