Ten years ago, a fun monetary mystery fell into the hands of scientists and students at the Pontifical Catholic University of Peru in Lima.
The university was purchasing 19th- and 20th-century Peruvian coins from local dealers, and graduate students in the chemistry department were analyzing the pieces for their thesis work. But one coin, a 10-cent coin known as a coin, stood out.
The money was marked “1899”. The problem was that official documents indicated that no coins of that denomination were minted in Peru that year: according to the people who created the coin, the coin never existed.
Most international coin catalogs do not list coins from 1899, said Luis Ortega, a chemist at the university. And in the rare cases when this happens, there is often just a “counterfeit” note with no further details, Dr. Ortega said. “No one has been able to provide more information on that.”
Now Dr. Ortega and PhD student Fabiola Bravo Hualpa believe they have shed new light on the mystery of the coin that came from nowhere. In an article published last year in the journal Heritage Sciencedescribed how they subjected one of two known 1899 funds to a barrage of scientific analysis, illuminating its possible origins and the role it might have played during a volatile era in South American history.
To the naked eye, the 1899 coin resembles other coins: it is silver in color and features the same coat of arms and the seated woman representing the goddess of freedom. And it is remarkably similar in size to other coins minted in the early 20th century: about the size of an American dime.
But when Dr. Ortega and Ms. Bravo Hualpa bombarded the 1899 coin with X-rays and measured the light it emitted, they determined that the coin was largely composed of copper, zinc and nickel. This alloy is known as nickel silver. It is commonly used to make silverware and ornamental items and has a silvery appearance, but contains no silver. Authentic coins produced by the Lima Mint, however, are made up of approximately 90% silver.
Dr. Ortega and Mrs. Bravo Hualpa also discovered that the 1899 money contained traces of iron, cobalt and lead. Such impurities imply that the coin was counterfeited a long time ago, not more recently, the researchers suggest. Such contaminants are characteristic of older alloys due to the technological limitations of the time. “The refining methods were not as good as they are now,” Dr. Ortega said.
The presence of impurities, combined with the coin’s worn faces, suggests it was produced in the 19th or 20th century, the researchers concluded. But given that nickel silver was not widely used for coins or tokens in Peru at the time, it is likely that this coin was created overseas, the researchers suggest. Its manufacturer may therefore have been completely unaware of the fact that no coin was officially minted in 1899.
“The counterfeiter probably didn’t realize that coin didn’t exist,” Dr. Ortega said.
He said an influx of low-value coins would be welcomed in Peru at the dawn of the 20th century. The country’s economy was reeling from the recent Pacific War, and the government was focusing on printing larger denomination paper banknotes to repay international loans; In 1899, the Lima Mint produced approximately one-tenth the number of silver coins produced just five years earlier.
As a result, people in Peru used coins from neighboring nations or even cut their own country’s coins in half to make small transactions. “Counterfeiters have found a field of opportunity,” Dr. Ortega said.
Dineros were low-value coins used by common people. The study of this currency and the economic and political situation that led to its creation can therefore be enlightening. “If you want to study our society, you don’t want to look at a Ferrari,” said Laura Perucchetti, an archaeometallurgist at the British Museum in London, who was not involved in the research. “You want to look at a Volkswagen or a Ford.”
Dr. Ortega has not finished studying counterfeit coins and their historical context. He plans to meet with a Lima-based collector who has amassed an assortment of coins apparently minted from the 1930s through the 1960s. Another 1899 denarius has already surfaced in that collection, and he is looking for more.
“There must be some of them around,” Dr. Ortega said.