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V14 2011 INDEX E-SYLUM ARCHIVE

The E-Sylum: Volume 14, Number 52, December 18, 2011, Article 10

In the spring of 1964 I visited Oak Ridge of a field trip with my physics class. We were allowed to make an irradiated dime with the machine that is pictured in the December 11 E-Sylum. I remember dropping the coin in the slot and watch it go through the machine. If Oak Ridge started making them in the 40's there should be a large number of these dimes in drawers somewhere. I would suspect mostly in the southeast.

Some time during the summer of 1952, Mom and Dad took myself and my sister to the Museum of Atomic Energy at Oak Ridge, Tenn. We lived in Jefferson City, Tenn. at that time while Dad attended Carson-Newman College. I was eleven at the time and vaguely remember the trip, but I do remember getting the irradiated dime. My sister, who passed-on several years ago, got one also. I have both souvenirs today but the dime is missing from one of the holders. I do not know which of these is mine or my late sister's. The remaining dime is dated 1944 and I believe the other was a Roosevelt.

This is the era when I started collecting coins. Mom was the one and only City Clerk at the time. Once a week the two city police officers would rob the one hundred or so parking meters and Mom and Dad would help count and roll the coins. I got a lot of pennies and a few dimes and nickels to start my collection. As the coins were counted, they would hold out the coins that looked old. I have often wondered how many early dates that looked new got away. Dad graduated in 1954 and we moved to Cosby, Tenn., moonshine capitol of East Tennessee, and that my friends is a whole 'nother story as Dad was a preacher.

Regarding the "irradiated dimes" I have several in my encased collection. The 'winged liberty' one I have still has the plastic lens over the coin, many do not. There is no known census of the coin and they regularly sell on Ebay for $10 or so. there is also a blue plastic "irradiated" dime from the 1964 World's Fair. These are not as common and sell for around $15-$20.

"The Neutron Irradiated Dime, Atomic Energy Commission, New York World's Fair, 1964-1965" by Stephen P. Alpert, TAMS # 2134.

"The illustrated encased dime originated from the U.S. Atomic Energy Commission's exhibit in the Hall of Science, a pavilion in the Transportation Area of the 1964-1965 New York World's Fair.

To obtain this souvenir, the visitor deposited his dime into a very narrow machine with transparent sides. The dime rolled down a chute into the area where it was irradiated for a few seconds. It was then ejected via another chute, into a tray at the end of the machine. A Geiger counter nearby demonstrated the radioactivity of the silver dime. The attendant, wearing protective gloves, then snapped the dime in the plastic holder and handed you your souvenir.

The holder is blue plastic with white incuse lettering and design, and is 48mm in diameter."

The article is accompanied by an example of a 1960 Roosevelt dime in the plastic holder (front & back view).

As a high school freshman in NYC at the time of the World's Fair, I visited it many times. During one of my visits, I had a dime irradiated at this exhibit. One problem was that the dime could easily be popped out of the holder & spent (as my younger brother eventually did with his). Likewise, another dime could then be reinserted. So, there is no way to guarantee that the dime in a holder today is the irradiated dime. I read somewhere that the radiation dosage was so low and the half-life so short the dime would no longer be radioactive.

Here are scans of my irradiated dime from the NY World's Fair. It is a 1948 Roosevelt dime. I have never removed the dime, so it is the one that I had originally had irradiated.

Here is a scan of my 1951 Roosevelt neutron irradiated dime by the American Museum of Atomic Energy. The reverse is blank. I purchased it from a coin dealer in February 1998 for $5.00.

Besides the previously mentioned TAMS article, there was an excellent article (which is too long to copy) in Coin World on the irradiated dimes. It's entitled, "Dimes tell Oak Ridge story" by Michael E. Marotta. COIN WORLD, Monday, October 4, 1999, pp. 20 & 28. The article discusses the dimes irradiated at both the museum & the NY World's Fair and is accompanied by pictures of a number of irradiated dimes.

There was also another article on irradiated dimes, entitled "Fallout In Your Pocket." in Rochette, Edward C. 1985. The Other Side of the Coin. Frederick, CO: Renaissance House. pp. 72-73. Accompanying the article is a picture of an encapsulated "1962 "Cadmium'" dime. There is one part of the article which discusses the irradiation process at the museum.

". . . He [T.F.X. McCarthy, then information officer, Oak Ridge Institute of Nuclear Studies] assured me that only a few atoms of the dime's silver had been made radioactive during its exposure in the radiation device and that silver loses its radioactivity at such a fast rate that the dime would 'probably' fail to register on a Geiger counter by the time the visitor leaves the museum.

Making dimes radioactive was discontinued only when silver coins disappeared from circulation in the mid-1960s. When exposed, the silver in the dimes changed from Ag-109, which absorbed neutrons very easily, to AG-110, which is radioactive. The dimes, for about four minutes, were capable of emitting low-energy beta radiation. After 10 half-life periods, less than a tenth of one percent of the original activity remained and could be detected only by highly sophisticated equipment. . . . the exposed silver transformed itself into stable Cadmium-110."

Based upon the foregoing, I find it hard to believe that "If you have a Geiger counter you can confirm this! Indeed, this was done at an early Fest" as was stated in an earlier Esylum." For this to occur, that dime had to be hit with a LOT more radiation than was being used. I would guess the Geiger counter used at the Fest was picking normal background radiation and not radiation from the dime. Indeed, if you turn a Geiger counter on (as I have done in my geology classes), every now and then it will click. That is from normal background radiation.

To read the earlier E-Sylum article, see: IRRADIATED DIMES (www.coinbooks.org/esylum_v14n51a07.html)

Wayne Homren, Editor