
Detail of eye on page 6 of the Grolier Codex (photo by Michael Coe, all courtesy Brown University)
In the 1960s, looters searching a cave in Chiapas, Mexico, came across a rare, ancient codex rich with illustrations of weapon-wielding deities. The 13th-century manuscript ended up in the hands of Mexican collector Josué Sáenz, whose story would make a good art crime thriller. Sáenz claims he had received an invitation from an unnamed person to hop on a plane that deposited him on a remote airstrip in Chiapas, where he was presented with the codex. It eventually went on display in 1971 at New York City’s Grolier Club, the organization from which it takes its present-day name: the Grolier Codex. Archaeologists have since been butting heads over its authenticity, largely due to its cryptic emergence and the number of forged Maya codices that have come to light.

Page 6 of the Grolier Codex, with drawings of underpainting by Stephen Houston (photo by Enrico Ferorelli) (click to enlarge)
“This book may well be the guide of a trained Maya ritualist, literate in both complex imagery and calendrics,” the research team of Michael Coe, Stephen Houston, Mary Miller, and Karl Taube write in the paper. “Features of the codex — although not the glyphs — show great sophistication and knowledge of iconographic motifs.”
The codex would originally have had around 20 pages, and the remaining half — though still partially hinged together — has suffered water damage with some loss of imagery. But what remains still allows for in-depth examination, and the researchers present thorough and compelling evidence considering many aspects of the artifact. The codex, they argue, simply cannot be the handiwork of a mid-20th-century forger (or, more reasonably, a team of forgers) because its maker had to have access to the right amount of amatl, a paper made from the inner bark of fig trees — which was pre-Hispanic in origin — and know how to properly glue and bind the material into a concertina format. Many forged codices, they write, tend to appear on deer vellum.
Painted on just one side, the Grolier Codex boasts dynamic scenes of gods, with even human captives appearing on some pages. The research team also considers its artist’s style of illustration, noting that how the codex-maker sketched lines and grids to arrange his figures in a way that reflected similar strokes seen in other Maya paintings. The proportions of their fully-shown bodies, represented in profile or frontal formats, also adhere to renderings found on the three authentic codices and other portable artifacts and carved ceramic vessels of the time. Even small details, like the lines forming the figures’ eyes and earlobes, are characteristic of contemporaneous, ancient representations.
“The artist has a practiced and learned skill in rendering the arm and hands, showing depth and movement, while the depiction of the face is consistently flat and uninflected with any sense of depth, except for the slight curl to indicate the nostril,” the paper reads.

Detail of page 4 of the Grolier Codex showing underpainting (photo by Justin Kerr)
When the looters came across the codex in the ’60s, they apparently found it with six other objects, including a child’s sandal and wooden boxes. Five of these are currently in museums — the child’s sandal is now lost — having been proven genuine, which the researchers say bolsters the case for the Grolier Codex’s authenticity. Considering its make, accurate iconography, and distinct style, they write, the manuscript must have also survived centuries of weathering rather than existing as an intentionally damaged publication by forgers — who would have succeeded in their craft only if they had access to expert knowledge published in rare or largely inaccessible scholarly tomes.
But others remain skeptical of these recent conclusions. Archaeologist and criminologist Donna Yates — who notes on Trafficking Culture that Coe had organized the 1971 exhibition and later called the lent codex a “real hot potato” — firmly believes that the manuscript’s problematic provenance will always be an issue. One gap in the new study, she writes, is that the radiocarbon dating that dates the Codex to between 900 and 1250 CE only accounts for the paper rather than the images.
“The authors present a very strong case for the authenticity of the Grolier Codex,” Yates concludes. “Yet, even if it is authentic, because it was looted and trafficked, questions will remain. If the piece had been archaeologically excavated, there would be no need for such an intense focus on authenticity.”

Page 8 of the Grolier Codex, with drawings of underpainting by Stephen Houston (photo by Enrico Ferorelli)

Page 9 of the Grolier Codex, with drawings of underpainting by Stephen Houston (photo by Enrico Ferorelli)