If it's slightly smaller than a quarter, then it's probably a Louis Philippe 1-franc coin minted from 1832-1846. In that condition, it's probably only worth melt.
4 half reales, 3 colonia, and one first republic. When these coins were demonetized in the USA they were turned over for the new copper nickel flying eagle cents, those coins were melted and used for regular USA issue coinage. These must have not been turned in.
What's especially cool about that piece is that it has been in the family for 110 years-- one of my great aunts actually attended the Pan-Am Exposition and that was one of her souvenirs from the event. I don't know if she was there on the day when President McKinley was shot (which was 110 years ago this month). http://en.wikipedia.org/wiki/Assassination_of_William_McKinley
Those Bust half dimes are really cute coins, and they are one of the very few 19th century series that can be completed for a reasonable price-- only 9 coins are needed to complete the set, and there are no great rarities. I've got 4 of them, am looking to get the other 5
1937 Washington Quarter DDO ??? I pulled this one from roll in the 1960's I pulled this one out of bank roll a very long time ago!!! it just been in my extra date for Washington quarter book! some think it a DDO but a TPG could tell us for sure. :kewl: