NNP

Terry Amburgey, metal detectorist, recently wrote to Newman Portal “I was metal detecting at a city park. I dug up a piece of brass and threw [it] in my pouch. Took it home and cleaned it up. I saw some writing and numbers. My wife did some research and came across this paper.” The paper Amburgey refers to is “1860 Maranville Improved Pocket Coin Tester,” contributed to Newman Portal by Malcolm Mathias in 2019. We reported Amburgey’s find to Mathias, who responded enthusiastically.

“I’m excited to see the sixth known example of an 1860 Maranville Improved Pocket Coin Tester,” Mathias writes. “Maranville appointed an agent [in Philadelphia], Charles G. Imley, to help sell the new Coin Testers to the public.  Two of the previously known examples have ‘Charles G. Imley’ engraved on the face. Three of the previously known examples do not have the Imley engraving – they are blank in that rectangular area on the face of the coin tester, like yours, now the fourth known example of this type – making a total of six now known.”

These devices allowed users to verify the diameter, thickness, and weight of suspect U.S. and foreign coins. They are now collectible in themselves, and the rare 1860 Maranville detector is highly prized. A group lot in the 2018 Newman sale of counterfeit coin detectors, including an example of the 1860 Maranville device, realized $12,000.

Link to Malcolm Mathias’s publications on Maranville Coin Testers: https://nnp.wustl.edu/library/booksbyauthor/534837
Link to Eric P. Newman example of the 1860 Maranville Coin Tester: https://nnp.wustl.edu/library/imagedetail/607680