Rare Spherical Specimen of Graphite from Chicago Pile 1 - CP-1 - Nuclear Reactor

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Rare Spherical Specimen of Graphite from Chicago Pile 1 - CP-1 - Nuclear Reactor:
$8000.00

This listing is for a rare spherical specimen of graphite from the world's first artificial nuclear reactor called Chicago Pile 1 (CP-1).

Samples from the Chicago Pile 1 nuclear reactor experiments are extremely rare and very difficult to find.

I purchased this at an estate sale in Hinsdale, Illinois.

It was on a table along with a bunch of other small items.

I initially thought it was a mineral sample in the form of a paperweight.

One of the workers at the estate sale mentioned to someone else that the owner of the house worked for Argonne National Laboratory.

That was later substantiated by a collection of books in the basement on nuclear energy that I now regret not grabbing.

The object itself is a free standing sphere that rests on a wooden base.

The graphite sphere weighs 6.85 oz. or 194 grams and measures roughly 2 1/8 inch in diameter.

The base is about 1/2 inch tall and 2 1/2 inch in diameter.

It has a green felt bottom and has an engraved plastic plaque glued to it that reads “C.P. 1 GRAPHITE”.

I’ve since learned that CP-1 was the world's first human-made, self-sustaining nuclear reactor, built by scientists at the University of Chicago under the direction of Enrico Fermi. The success of this project was the first real step in developing atomic weapons during the Manhattan Project.

The graphite was one of two major components of the nuclear reactor. The other being uranium.

45,000 bricks of graphite were produced for the reactor.

Because of the historical significance of CP-1, there is an abundance of information online but actual samples of CP-1 graphite are quite rare. Samples encased in lucite were produced at some point but I believe this spherical sample predates those samples.

I originally thought the spherical shape was just an interesting way to display the historic graphite.

But after watching the video below created by Argonne National Labs (created exclusively with lego blocks!), it appears the spherical shape was pivotal in the success of the first reactor. It turns out that the reactor only achieved “criticality” once the graphite bricks were arranged in a spherical shape so machining this sample in a spherical shape might have been quite intentional.

Below is an Antiques Roadshow clip of a nuclear scientist who owned a full brick from CP-1.

Shy of finding a full Chicago pile 1 brick, this is likely the largest specimen of graphite from the CP-1 reactor available to the public, not encased in lucite, and possibly one of the most tangible, non-ephemera based specimen of early nuclear history currently available for purchase.

After doing a little detective work, I was able to confirm that the owner of the house where this was purchased was Armando Travelliwho was a Senior Nuclear Engineer at Argonne National Laboratory.

It is my suspicion that this early specimen was gifted to him by someone who worked on the original CP-1 project or possibly someone further down the chain of command.

Lastly, I have a neighbor who shared the video and a photo from this listing via text to a retired Fermi Lab employee and he shared the following:

“This looks like a piece of graphite machined to a sphere as part of a memento (in place of just a plaque) given to someone who either worked on the project and retired, or were a major contributor. C.P.1 was Critical Pile-1 which was the experiment at the University of Chicago under the football field (Stagg) which demonstrated that a nuclear reaction was possible, leading to the Manhattan Project. The graphite used in that experiment was machined into blocks to slow down neutrons, this was probably part of the excess graphite that they had on hand.”

This item will be carefully packaged, insured and require a signature upon delivery.

Please check the photos for the exact items you will receive.

Thanks for looking and feel free to ask me questions.