Vinland Map: Yale Found a Pigment First Sold in the 1920s

What did Yale announce in 1965?

In 1965 Yale presented the map with a scholarly book, The Vinland Map and the Tartar Relation, by R. A. Skelton, Thomas E. Marston and George D. Painter (Exhibit B). Yale News recalled in 2021 that the announcement caused a sensation and seemed to show that Norse sailors had reached the New World before any other Europeans (Exhibit A). The book’s authors argued firmly for the map and linked it to the Council of Basel, a church council that met from 1431 to 1449 (Exhibit G).

The map did not arrive alone. When it reached Yale, it was bound inside a slim manuscript called the Tartar Relation, an account of a 13th-century journey to the Mongol lands, in a modern binding (Exhibit A). Yale later acquired a third item, part of a medieval encyclopedia called the Speculum Historiale. Yale’s copy of that volume is dated to the time of the Council of Basel.

A small detail from Yale’s copy of the Speculum Historiale, written around 1440. This genuine medieval volume is the likely source of the map’s parchment, by Yale’s 2021 account (Exhibit A).

Doubts came early. Writing in the Journal of Navigation in 1966, M. W. Richey noted that an antiquarian bookseller in New Haven, Connecticut, had found the map, and that the circumstances had so far blocked a proper look at its history (Exhibit C). In other words, its provenance, the record of who owned it and when, was missing. Richey also called the date of about 1450 provisional, and added that a genuine map would be the earliest surviving map of any part of the Americas.

From then on, Wallis wrote in 1991, specialists argued over the map in many publications and conferences (Exhibit E). This site retries the same pattern, acceptance by well-known names and the long argument that follows it, in the Cottingley fairy photographs.

What did the ink tests find before 2021?

The first decisive-looking result came from the ink. A 1973 study by McCrone Associates found anatase in it, a titanium dioxide that did not enter commercial use until the 1920s (Exhibit A). Walter and Lucy McCrone published the finding in The Geographical Journal in 1974 (Exhibit D). Those tests sampled specific points, not the whole map.

How Brown and Clark described the map’s drawn lines in 2002: black carbon ink lying on a yellowish line that contains anatase. A schematic, not a picture of the map (Exhibit F).

Later work kept pointing the same way. In 1991 Helen Wallis, a former head of maps at the British Library, summed up the analyses made in Europe and the United States since 1968: the ink resembled no known medieval ink, and the map appeared to be a fake, though she called for more study (Exhibit E, in French). Not every analysis is retold here. A 1987 study of the inks and parchment by T. A. Cahill and colleagues, and a 1988 paper by Walter McCrone, were read only as bibliographic entries (Exhibits O, P).

In 2002 the chemists Katherine L. Brown and Robin J. H. Clark used Raman microprobe spectroscopy, which reads a material’s chemistry from scattered laser light. They found that the black ink of each feature lies over a yellow line containing anatase, a layer they did not find elsewhere on the map (Exhibit F). A modern, post-1923 origin, they wrote, was strongly indicated.

The case was not closed. In 2003 Jacqueline S. Olin published “Evidence that the Vinland Map is medieval” in Analytical Chemistry (Exhibit I). She argued that carbon was sometimes added to medieval inks, and that anatase could come from the way medieval inks were made. Replies came in the same journal in 2004, including Kenneth M. Towe’s “The Vinland Map Ink Is NOT Medieval” and a rebuttal from Clark (Exhibits J, K).

One more study looked at the whole sheet before Yale’s. In 2004 Danish scientists measured the map’s colour, thickness, flexibility and transparency, and assessed damage to its parchment (Exhibit A). Yale News reports no finding on authenticity from that work.

How old is the parchment?

The parchment is old, and nobody in this record disputes that. In 2002, D. J. Donahue, J. S. Olin and G. Harbottle dated it by radiocarbon to AD 1434, plus or minus 11 years (Exhibit G). At 95 percent confidence the range is AD 1411 to 1468.

In a comment in the same journal, K. R. Ludwig argued that the separate measurements scattered more than the stated error allowed (Exhibit H). His point was about the size of the error margin, not the century.

Yale’s own radiocarbon tests in 2018 dated the parchment and paper of the two companion manuscripts to about 1400 to 1460 (Exhibit A). A watermark in the Speculum Historiale traces to a paper mill that worked in Basel in the 1440s. The text of both manuscripts is written in a similar hand, likely by the same scribe. The parchment, the paper and the handwriting all fit the mid-1400s.

Two stretches of time, with the gap between 1475 and 1915 cut out. Left: the dates of the parchment, the companion books and the Basel watermark. Right: titanium white pigments of the 1920s, the 1923 Norwegian pigment, and the map’s modern history (Exhibits A, G).

But a radiocarbon date belongs to the skin, not to what was later drawn on it. An old blank sheet can carry new ink.

The ink sets the earliest date the drawing could have been made, a limit known as a terminus post quem: an object can be no older than its newest ingredient. If the drawn lines hold a pigment first made in the 1920s, the drawing dates from the 1920s or later. The parchment’s central date, 1434, is 489 years older than the 1923 pigment that the map’s anatase was later found to resemble.

What did Yale find in 2021?

Yale’s 2021 team paired two Yale University Library conservators with scientists from Yale’s Institute for the Preservation of Cultural Heritage (Exhibit A). Unlike earlier testers, they had open access to the map and both companion manuscripts for as long as they needed. Their main tool was macro X-ray fluorescence, or macro-XRF, which maps the chemical elements across a whole flat object.

The conservators were Marie-France Lemay and Paula Zyats. The scientists included Anikó Bezur, Richard Hark and Pablo Londero (Exhibit A). X-ray fluorescence had been used on single points for decades. Only recently, Bezur said, had it become possible to scan a whole flat object this way in a laboratory.

Where the ink was tested: nine points in the 2002 Raman study, and the whole sheet in Yale’s 2021 scan. Blank sheets in the map’s proportions; no map is drawn, and the point positions are schematic (Exhibits A, G).

The scan found titanium throughout the map’s lines and text. Look at what it did not find: little or no iron, sulfur or copper, the elements expected in iron gall ink, the usual ink of medieval scribes. Over the Vinlanda Insula coastline, the scan showed high titanium with smaller amounts of barium. Titanium white, as first sold commercially in the 1920s, mixed titanium dioxide with barium sulfate.

Three more steps bear on the objection raised in 2003. Raman microscopy showed the titanium in the ink is anatase, spread broadly over the sheet rather than at a few points. The inks of 50 manuscript fragments made in Central Europe in the 15th century held far less titanium and much more iron than the map. Under an electron microscope, the map’s anatase particles closely resembled a pigment made commercially in Norway in 1923, and nothing suggested a natural source.

Illustration

An illustration of an imagined scene of the kind of work behind Yale’s 2021 re-examination: a conservator lays a parchment sheet flat for a scan of the whole sheet. Not a picture of the Vinland Map or of Yale’s laboratory.

“The Vinland Map is a fake,” said Raymond Clemens, Yale’s curator of early books and manuscripts (Exhibit A). This page follows Yale’s 2021 finding because it is the only ink analysis that covered the whole sheet, compared the map with 15th-century inks, and found the pigment closely resembled a dated modern product. The earlier point tests from 1973 and 2002 are consistent with it; Olin’s 2003 argument is the reading it answers.

The record of 2021 has limits of its own. It comes from Yale News, the university’s news office, reporting on work done in Yale’s own laboratories on an object in Yale’s own library. The team said it planned to publish the details in scholarly articles, and this page has not read a technical report. The findings above are given as Yale described them.

Was it made to deceive, and who made it?

Modern ink was not all Yale’s team found. On the back of the map was a short Latin note in iron gall ink, possibly a bookbinder’s note about where a section of the Speculum Historiale belonged (Exhibit A). Someone had written over it in titanium-containing ink, so that it read like an instruction to bind a drawing into the medieval volume. Infrared light also showed altered text in the Tartar Relation, and the altered text is in modern ink.

The Speculum Historiale is a large work of 32 sections, usually bound in four volumes. Yale’s copy holds books 21 to 24, the second half of the third volume, and the original note fits that copy (Exhibit A). A 14th-century copy of the complete work found in Lucerne, Switzerland, has a Tartar Relation bound into its last volume, so the two texts had been bound together before.

How the three items fit together, by Yale’s 2021 account: matching wormholes place the map at the front of the Speculum Historiale, likely on an end sheet; it reached Yale inside the Tartar Relation. A diagram, not a picture of the objects (Exhibit A).

The team’s scientists read the altered note as evidence of a motive to deceive. By Clemens’s account, it shows a forgery rather than an innocent drawing later passed off by someone else, but it does not say who made it.

Yale’s 2021 announcement names no maker. This page treats the maker as unknown. A 2006 article by P. D. A. Harvey in Imago Mundi, titled “The Vinland Map, R. A. Skelton and Josef Fischer” (Exhibit M), was read here only as a bibliographic entry, and its argument is not reported. The same question, what is in the paint and when could it have been made, comes up in the case of Han van Meegeren’s paintings.