By Robert Rodriguez and Tony Lopez – 1792 Silver Disme Project ……
After nearly four years of research, the 1792 Silver Disme Project is nearing completion. To complete this project, in January, the Resolute Americana Collection acquired the lone 1792 silver disme it did not own, the Judd-9a thick planchet. As such, for the first time since the 1792 Mint, all three 1792 silver dismes reside in one collection. Nearly $1.9 million was expended to acquire the necessary coins for this research study.
Since early 2016, the team of Rob Rodriguez and Tony Lopez has been studying the Judd-9, F15 NGC, thin planchet silver disme. For over 150 years, it has been described as “marked-up,” “scratched,” or “graffiti.” When I first saw this coin, the etch marks conveyed something totally different to me and I believed they reflected a hidden story. To unravel this mystery, Tony Lopez joined the research effort and brought his considerable photographic talents to it.
The Judd-9 F15 has been subjected to approximately 1,000 hours of study that includes over 150 hours of photographic analysis, 55 hours of scanning electron microscope analysis, utilizing two different types of SEMs, and, finally, over 470 hours of X-ray diffraction at the Argonne National Laboratory Advanced Photon Source (APS) synchrotron.
The APS is one of the premiere synchrotron particle accelerators in the world. After an application process that took several months, this project was accepted–a first for numismatics.
As a result of its success, this project demonstrates how high intensity X-ray diffraction can be utilized upon rare metallic antiquities without fear of harm to them. It can recover information that was previously thought to be permanently lost.
In four visits to the APS in 2018 and 2019, we were able to recover accurate images of virtually 100% of the lost or disfigured surface markings from a depth of approximately 20-25 microns.
These etch marks were burnished away or distorted by Edward Cogan’s attempt to “improve” the surface appearance of the coin. In January 1864, the coin was sold to Mr. Edward Seavey for the incredible sum of $205 and it has been included among some of the great numismatic collections since 1864, including Lorin Parmelee; H.O. Granberg; Waldo Newcomer; “Col.” E.H.R. Green; Eric Newman and Burdette G. Johnson; Floyd T. Starr and Bob Simpson.
This April, we will be returning to the Argonne APS to subject the Judd-9a to X-ray diffraction testing. Dr. Wenjun Liu believes two visits may be required to scan all the necessary areas. We believe this coin, with its obverse tooling marks in front of Liberty and the removal of its date may have been part of the design work surface process that we have been investigating. We hope to recover the lost information that may provide additional insights about both coins.
Soon, Tony Lopez and I will begin the process of memorializing the research conducted and its discoveries, in a paper titled, “History Recovered, Saga of the 1792 Silver Disme.” We believe the numismatic community and the general public will find this story and its conclusions to be quite fascinating. Our journey of discovery took many twists and turns, with several challenges along the way, before achieving a successful outcome.
Special thanks and appreciation go out to the staff of the Argonne National Laboratory for their incredible support of this project. In particular, we could not have attained a successful outcome without the incredible talents of three physicists, Dr. Liu, Dr. Jon Tischler, and Dr. Ruqing Xu, who conducted the X-ray diffraction testing. The Argonne National Laboratory is an American treasure where leading-edge scientific investigations occur every day.
