The Vinland Map, a source of curiosity and controversy since it entered the public consciousness a half-century ago, is spread out on a table at Yale’s Institute for the Preservation of Cultural Heritage (IPCH) underneath a geodesic-dome cage.

An array of cameras and lamps affixed to the dome will photograph the parchment map’s surface as light projects from different angles. The digital photos will be compiled using special software, creating a dynamic image that shows the map’s surface texture from dozens of lighting angles. The images will allow people to study the topography of the map’s parchment. A miniature version of the dome will allow researchers to explore the thickness and morphology of the map’s ink lines from a computer screen.

The images could reveal information about the map, which purports to be a 15th-century world map with a pre-Columbian depiction of “Vinland,” a section of North America’s coastline southwest of Greenland. Reflectance transformation imaging, or RTI, is part of a new scientific analysis of the map under way at IPCH’s laboratories at Yale’s West Campus to better understand its material composition and the relation of these materials to two medieval volumes with which the map was bound: part of Vincent de Beauvais’s encyclopedia, “Speculum historiale,” and the “Tartar Relation,” a history of the Turks, Mongols, and Tartars.

The results of the analysis, which includes a battery of non-destructive testing, will be published in a book about the map being edited and compiled by Raymond Clemens, curator of early books and manuscripts at the Beinecke Rare Book & Manuscript Library, where the map resides. In May, the map will go on exhibit for the first time in more than 50 years as part of an exhibition on Vikings at the Mystic Seaport titled, “Science, Myth, and Mystery: The Vinland Map Saga.” The IPCH analysis will help inform the exhibit.

Yale sparked a sensation in 1965 when it announced the Vinland Map’s existence and published a scholarly book about it by Yale librarians and curators at the British Museum. The map, if genuine, would have shown that Norsemen were the first Europeans to reach the New World, landing in North America centuries before Christopher Columbus.

The university held the map’s unveiling on the day before Columbus Day. The revelation triggered outrage among New Haven’s Italian-American community, which celebrated Columbus as an emblem of Italian culture and a hero of the European Age of Discovery. (Archeological discoveries at L’Anse aux Meadows in Newfoundland confirm that the Vikings had settlements in the Americas long before Columbus set sail.)

Scholars immediately questioned the map’s authenticity, and an overwhelming consensus emerged over the years that the map is a 20th-century forgery. The current analysis is not intended to prove or disprove whether the map is genuine or refute past analyzes of it, but aims to expand scholarly understanding of the object.

“We’re trying to push the research on the map a little further,” said Anikó Bezur, the Wallace S. Wilson Director of Scientific Research at IPCH, who is directing the analysis. “We’re trying to better understand its materials — the chemical composition of inks and the origins of the parchment.”

Mapping the map

The full map was last examined in 2004 by scientists from the Royal Danish Academy of Fine Arts, School of Conservation, and the Royal Library in Denmark, who measuring its color, thickness, flexibility, and transparency while assessing damage to its parchment.

The current analysis includes several techniques, such as RTI, never before applied to the map. Multi-spectral imaging with ultra-violet and infrared light will provide information concerning the optical properties and chemical composition of the inks.

While previous testing examined individual points on the map, technology available at IPCH will enable the analysis of whole swaths of it, Bezur said.

For example, elemental mapping with x-ray fluorescence spectroscopy (XRF) will show the spatial distribution of elements along the map’s two-dimensional surface — both for the entire map as well as specific areas of interest.

Researchers will mine the data produced by XRF mapping and multispectral imaging for patterns and then try to determine how those patterns relate to the appearance of the map’s features, Bezur said.

“We can see how different elements are associated with different features: which elements are present in the parchment; which elements are associated with its yellowish ink lines; and which ones are correlated with the black ink that is flaking,” she said.

The analysis includes repeating and refining tests using Raman spectroscopy, a technique that reveals details about the map’s molecular structure.

“Raman spectroscopy has been used on the map, but we have a system with smaller spot size, more accurate positioning, and the capability to capture molecular maps of regions of the map rather than just performing spot measurements,” Bezur said.

She called the mapping with XRF and Raman spectroscopy the most exciting and potentially productive aspect of the new analysis, as it will show if the map’s chemical composition is relevant to explaining its visible features.

“It is easy to doubt the relevance of a single spot measurement, but much harder to argue with a non-random pattern in the map’s chemical composition,” she said. “If a picture is worth a 1,000 words, then this chemical mapping is worth at least 30 times more than that.”

Inks, parchment, and wormholes

Clemens, an expert on early maps, is interested in the analysis of the inks used in the map’s text as opposed to its geographical depictions.

“There is text on the back of the map that comes from the medieval book that its parchment was taken from,” he said. “I’m curious to see how the ink in that text compares to the ink used on the map’s text. Are they two different inks that were made to look the same?”

A 1973 analysis of the map by the McCrone Research Institute in Chicago, which also has analyzed the Shroud of Turin, detected the presence of anatase, a form of titanium dioxide first available in pure form in the late 1920s, indicating the map was a modern invention, though some experts contest the accuracy of that analysis. The latest round of Raman spectroscopy testing should produce higher-quality data based on an entire letter or line segment, instead of a single point, Bezur said.

Skeptics of the map’s legitimacy note that the map’s depiction of Greenland as an island — a fact that was not known in the 15th century— as evidence of forgery. They assert that various anachronisms in the map’s text, such as a Latin spelling of Leif Ericson’s name more consistent with 17th-century norms than medieval spellings, cast doubt on the map’s authenticity.

Radio carbon dating placed the origin of the map’s parchment between 1423 and 1445, according to a 2002 study. Wormholes in the parchment align with wormholes in the companion volumes. A test at IPCH using Mylar tracing paper confirmed the wormholes’ alignment, which shows that the map’s parchment and two books were once bound together but does not demonstrate anything about when the map was drawn, Clemens noted.

Small samples of the map and the two manuscripts will be sent to the University of York in England for DNA analysis to possibly determine the geographical origin of the animals used to make the parchment. Peptide mass fingerprinting will be conducted on the manuscript samples to determine the type of animal used to create the parchment. Earlier testing on the map determined its parchment was made from a cow.

“Do the animals used for the parchment of these three documents come from the same region in Europe?” Bezur said. “What else can we learn about them?”

A continuing conversation

Clemens believes the map is a modern forgery and his reasoning is simple: Medieval people did not tend to view the world pictorially.

“There really aren’t medieval maps in the way that we have maps today,” he said. “They didn’t think of travel using graphic maps. Travel was literary. You were 12 miles from this town, which was 12 miles from this town, which was 10 miles from a port. Travel documents were generally written.”

Why were people taken in by it? Why was the reaction to it so strong? Raymond Clemens

Nordic sagas describe voyages to North America, but it is unlikely anyone would have documented those travels on a map, he said, adding that Columbus relied on ancient Ptolemaic maps.

Clemens noted two additional reasons he believes the Vinland Map is a fake: First, the map’s creator did not account for the fact that the map would be bound and information on it would be buried in the book’s gutter — the inner margin separating the pages.

“Maps bound into books would be overdrawn to account for the space lost in the gutter,” he said. “The rest comes together and looks nice. Other than the Vinland Map, I’ve never seen a map drawn on a single piece of parchment that was simply stuck into a book. That doesn’t make any sense because a lot of information would be trapped in the gutter and nobody would see it.”

Second, the map, which is based on a world map by 15th-century Italian cartographer Andrea Bianco, is off-center. Vinland, Greenland, and Iceland are added to it, but no effort was made to create a centered and proper map of the world, he said.

“Almost certainly the mapmaker would have included those land masses as part of the world, not something tacked on outside of it,” he said.

Whether or not it is genuine, the map is a fascinating object that ought to be studied and shared with the public, not hidden away, Clemens said.

“I’m very interested in why it became such an important object,” he said. “Even as a fake, it has shown up in almost every historical atlas. They’ll say that it is assumed to be a fake, but it’s still there. It’s got a cultural purchase in some respects. Why were people taken in by it? Why was the reaction to it so strong?”

Good scholarship requires being open to all possibilities surrounding an object like the map, he said.

“We rightly ought to be skeptical of it,” he said. “Scholarship at its best allows us to have a continuing conversation as knowledge expands. We shouldn’t be afraid that the conversation undoes something, or makes us look stupid, or anything else. It’s a continuing process.”

By acquiring and publishing the map, Yale ignited a valuable debate that has broadened people’s understanding of the medieval world, Clemens said.

“In that process, we’ve learn a tremendous amount about mapmaking in the 15th century,” he said. “That was part of the problem: Most medievalists in the early 1960s didn’t know what a medieval map looked like. If you don’t have a concept of medieval mapping then an object like the Vinland Map could be very convincing. Fields grow and we learn.”

The team conducting the map analysis is composed of Bezur and her IPCH colleagues Richard Hark, a visiting professor from Juniata College, and Pablo Londero, a conservation scientist; and Marie-France Lemay, paper conservator; Karen Jutzi, conservation assistant; and Paula Zyats, assistant chief conservator, from the Yale University Library’s Preservation Department.

The Vinland Map will be on view at the Mystic Seaport from May 19 through Sept. 30. A companion exhibition, “The Vikings Begin,” opens the same day.