"The Alcatraz stamp is a fantasy. It purports to be from 1955 but is shown on a Series 1957B Silver Certificate.

"The 1957B Silver Certificates were delivered to the Treasury from the BEP between January and November 1963. Alcatraz ceased operating as a prison in March 1963."

"I remember seeing these on eBay and challenged the seller. I received a less than professional response. It was an easy thing to disprove."

"My attention was caught by the silver certificate overstamped with FEDERAL PRISON BANK OF ALCATRAZ 1955. When I see things like this they very quickly go into my "too cool to be true" file, along with bawdy house tokens, CSA dog tags and the like.

"While I haven't studied the subject of prisoner currency, and I can't say for certain that this overstamp is fake, there are a few things that arouse suspicion. First is the series date of the note. Granahan and Dillon served concurrently only from January 3, 1963 to March 31, 1965, so notes with these signature could not have been issued prior to the earlier date. The Alcatraz Federal Penitentiary closed March 21, 1963, so that offers an extremely narrow window of time in which a legitimate overprint could have been produced. If such an action had been taken during that two-month window, why would the stamp be dated 1955? Why would a note be stamped that way at all, unless it was to prevent prisoners from trading with outsiders? Were these notes limited to use by guards and other staff, and if so what could they possibly be buying at Alcatraz? It's almost certain that the guards were paid by check and that they would have to cash or deposit these checks on the mainland. It also seems unlikely that actual USA coins and notes would be in use; some sort of scrip or tokens would be much more likely.

"Finally, it seems that every person who ever had even the slightest connection with Alcatraz during its period as a federal prison has written a book about their experiences. I own or have read nearly all of these books and have taken the prison tour many times, and I've never seen any reference to actual money of any sort being used on the island."

"Thanks. I guess we'll have to delete it from the second edition."