Notes bearing a "Hawaii" overprint were used during World War II (July, 1942) to insure identification should they have fallen into enemy hands. Types of these notes (with brown seals and serial numbers) included $1 Silver Certificates and $5, $10, and $20 Federal Reserve Notes. It was not until October 21, 1944, that all currency restrictions were revoked and normal monetary conditions returned to that area.
The Department of the Treasury redeems all genuine United States currency at face value only, and does not render opinions concerning the numismatic value of old or rare currencies. If you wish to have your notes appraised, it is suggested that you look online for a private collector or dealer.
