Unfortunately they don't seem to know much about it. No price listed as it has been sold, but all the other fobs on the page seem to be $35. This was was gold plated...
As far as the history and patriotic movements and such... in an article posted on ancestory.com, George G. Morgan writes the following in his column, Clues Among the Family Jewels:
>>>In my own family, there are several interesting pocket watches. One gold watch belonged to my great-grandfather and is attached by a heavy satin striped ribbon to an 18K gold fob measuring two inches across that is the Great Seal of the United States, a memento of the Unites States' Centennial in 1876.<<<
