The festivities surrounding San Gennaro, celebrated with fervor in Naples, arouse both admiration and curiosity. The famous liquefaction of his blood intrigues the faithful and scientists. This phenomenon, which occurs three times a year, questions the very essence of this “miracle” and invites us to explore its multiple interpretations.
On September 19th, the miracle of San Genaro is celebrated: for the second time this year, what according to tradition is the blood of the Patron Saint of Naples and Campania should liquefy. Over the years, scientific hypotheses have also been formulated proposing alternative explanations for this phenomenon. Specifically, a 1991 study hypothesizes that in the ampoule there could be a mixture of substances with thixotropic properties.
September 19th is San Genaro Day, one of the most important religious holidays in Naples and one of the best known in all of Italy. Although the main celebrants are Neapolitans and Campanians, the fame of this commemoration has over time gone beyond the city’s borders, attracting the curiosity of many visitors, especially because of the famous “miracle” of the liquefaction of the blood of San Genaro. The quotation marks are in order, and we will see why. The event is highly anticipated: according to the cult, in fact, the non-liquefaction of the blood announces the arrival of bad news.
The « prodigy » of San Gennaro actually takes place three times a yearThe first time falls on the first Saturday in May, the second falls on September 19 and the third on December 16. All three events take place in the Duomo of Napleswhere the ampoules containing blood. However, that of September 19 is the most significant celebration because it coincides with the feast of the Patron Saint of Naples and Campania, to the point that schools and offices remain closed in Naples. September 19th in fact commemorates the beheading of the Bishop of Benevento in 302at the Solfatara of Pozzuoli, in the Phlegraean Fields. During the last celebration, the blood liquefied.
The story of his prodigy – the Catholic Church did not recognize the official classification of “miracle” – has also greatly intrigued the scientific community : there is no shortage of studies aimed at providing a scientific explanation to the phenomenon. One of the most significant is that carried out by the Cicapthe Italian Committee for the Control of Claims about Pseudoscience, founded in 1989 by Piero Angela.
What’s in the Ampule of San Genaro: Is it real blood?
The story of the miracle of the liquefaction of the blood of San Genaro is still full of shadows today. In the past, many people have put even doubts that it is real bloodespecially since, beyond hypotheses and theories, it has never been possible to analyze which has been celebrated for centuries as the blood of San Genaro. The first mention in ancient documents of the existence of this relic and the celebration that accompanies it goes back several centuries: in the Chronicon Siculusit is explained that the August 17, 1389there was a large procession to witness the miracle.
Let’s start by saying that the relic, that is, the so-called blood of San Genaro, is kept in a glass case containing two ampoules, one containing what for believers is the blood of Saint Gennarothe other being half empty because almost all of its contents were taken by Charles of Bourbonwho took it with him to Spain.
Concerning the nature of the content, the first important piece of information dates back to 1902, when the professors Sperindeo and Januario subjected the bulbs to spectroscopic analysis: the test confirmed the spectrum of oxyhemoglobintherefore blood. The same analysis was repeated in 1989: it gave the same result. However, another study, developed by Cicap, which we will discuss shortly, demonstrated that other substances could also liquefy and give the same result in this type of analysis, instilling doubt that what is found in the ampoules is not necessarily blood.
Why San Genaro’s Blood Liquefies: The Scientific Explanation
According to the faithful of San Genaroobviously, the liquefaction of his blood, which occurs during a solemn ceremony performed by the Abbot Treasurer, for more than ten years, by Monsignor Vincenzo De Gregorio, is the result of a prodigy. To call it a “miracle” is in fact not correct given that the authority of the Church did not recognize the fact that the blood of San Genaro liquefies miracle status. This is why it would be more accurate to use the expression “prodigy”. However, given the symbolic value that this rite has assumed for the faithful themselves, the event is awaited and celebrated as a miracle.
Since during the celebration of the miracle, the ampoule containing the alleged blood is shaken several times to allow liquefaction, the three scientists assumed that there was in the ampoule a mixture of natural substancesreadily available even in the Middle Ages, which resembled blood and had the property of liquefying if agitated.
The Miracle of San Genaro: Laboratory Experiments
The three researchers put forward their hypothesis after testing in the laboratory the possibility that an alternative substance to blood could become fluid if subjected to mechanical stress. In their work, the researchers prepared a substance using very simple componentswhich “are still found in nature and were certainly available to a medieval alchemist” – the first historical attestations of the relic date back to 1389 – namely carbonate de calcium (which makes up the shell of eggs), table salt et ferric chloridewhich is found in molisite, a mineral present in volcanic areas. The color of the compound was very similar to that of blood, moreover – explains Cicap – “the presence of iron would allow to interpret the results obtained by two spectroscopic analyses carried out on the relic in 1902 and 1989”.
The Mystery of the Liquefaction of San Genaro’s Blood
In reality, it should be clarified that even that of Cicap remains a hypothesis. The reason – explains the center – is quite clear: the last word on the true prodigious nature of the liquefaction could only be pronounced by directly analyzing the blood contained in the ampoule. This lack of certainty has led some to affirm that the mystery of San Genaro remains inexplicable even at the scientific level. In fact – specifies the Cicap – “there is no research published in a scientific journal that can corroborate this statement”.
