I recently found some of my dad's old coin collection, being a daddy's girl I could never give any of it up, but I have never seen anything like it before. Its very large, probably as big as two silver dollars put together, if not a little bigger. Could anyone tell me what it is, and if so, how much It would be worth?
This appears to be a commemorative, at least to me, rather than a coin. Tadeusz Kościuszko was a general during the American Revolutionary War, and the words appearing around the reverse of the coin are words written about him in correspondence from Thomas Jefferson I believe. Would like to help more but I can't find anything that looks similar to this.
Historical medals such as yours fall into the category of "exonumia", things similar or related to coins and currency. As such their value is either the bullion value if struck (or cast) in a precious metal, or their collectible value to people interested in the particular historical niche they occupy.
Tadeusz Kościuszko NYC has a bridge named after him, which links parts of the boroughs of Brooklyn & Queens.