Monroe Silver Co. History?

[MsJMoody]

I have this Yellowstone Park salt and Pepper shaker set marked Monroe Silver Co 453 in a fine/thin font.





I have found a F.S. MONROE JR. & CO but the font/style of the mark is not the same. (see here http://www.silvercollection.it/AMERICAN ... MPDUE.html )

I have also found Monroe Silver Co. in a few lists stating it was under International Silver Co. (inconsistently)

Does anyone have any more information on this company and when they operated?