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[N.B.:  The archeologically recovered objects, such as those described in this post, are still referred to as "Roman dodecahedron", but that is partly to distinguish them from the scientific study of such figures in chemistry, crystallography, geometry, mathematics, and so forth.  Considering the most recent archeological discoveries and studies, we will have to stop calling them "Roman dodecahedron" and may well have to begin styling them "Gallo dodecahedron" or at least "Gallo-Roman dodecahedron" (see below for the reasoning).

In geometry, a dodecahedron or duodecahedron is any polyhedron with twelve flat faces. The most familiar dodecahedron is the regular dodecahedron with regular pentagons as faces, which is a Platonic solid.

As if we hadn't spoken enough about dodecahedrons in the last few years!  Problem is, most of what we said was speculation, albeit interesting and ingenious, based on little other than the objects themselves — their odd shape, the locations where they were found, etc. — but there were no contemporary texts or associated artifacts / materials that would help us understand the purpose / use of these extraordinary, uniquely shaped objects.

But now we have a truly unprecedented discovery of a dodecahedron from a secure, sealed context.

"The Norton Disney Dodecahedron" (NDD) — with close-up photographs of the object.  The large, opening photograph, makes the front of the dodecahedron look like a face, with two holes for eyes on top, a knob for the nose in the middle, and one hole for the mouth at the bottom, though I'm not asserting that the makers of the NDD had that as one of their intentions.

The Norton Disney Dodecahedron

From the Norton Disney History and Archaeology Group:

We found a fantastic example of a “Gallo Roman Dodecahedron” in June 2023  One of archaeology’s great enigmas. It was found in trench 4 on our 2023 “dig” by one of our volunteers. Trench 4 had only been opened in the last few days of the excavation. No metal detector was used when it was found. As we had to close the trench shortly afterwards we needed to return in 2024 to better understand the context of this find.

There are about 32 known examples, either whole or in parts in Roman Britain. The Norton Disney example now makes 33. There are roughly 130 known examples across the Roman world. All of which are found in north west Roman provinces. The Norton Disney dodecahedron is the only example found in the Midlands and is a particularly fine example. It is well cast, complete with no damage and in an excellent condition. It is an example of very fine craftsmanship, finished to a high standard.

After it’s [recte its] discovery the dodecahedron subsequently underwent XRF analysis by leading archaeo-mettallurgist [recte metallurgist] Gerry McDonnell which revealed it is a copper alloy object. 75% copper, 7% tin and 18% lead. 

It is also an important find in that it was found “in situ”, where it was deliberately placed some 1700 years before with 4th century Roman pottery in some sort of excavated hole or quarry pit. The context of which will need more archaeological excavation to clarify in 2025.

There are no known descriptions of dodecahedra in Roman literature and therefore their purpose remains extremely unclear. They are not of a standard size, so will not be measuring devices. They don’t show signs of wear, so they are not a tool. Nor are they devices for knitting. A huge amount of time, energy and skill was taken to create our dodecahedron, so it was not used for mundane purposes, especially when alternative materials are available that would achieve the same purpose. The most likely use we think is for ritual and religious purposes.

According to the Lincolnshire County Council, the Norton Disney dodecahedron, a 1,700-year-old Roman* artifact discovered in 2023, measures approximately 8 cm (3 inches) in height and is about 8.6 cm wide. It is considered one of the largest examples found, roughly the size of a grapefruit, and weighs 245–254 grams. 

*VHM:  The Norton Disney dodecahedron may be said to be a Roman-era artifact, but technically it is not a Roman artifact, nor are any of the known 130 +/- archeologically recovered dodecahedra Roman artifacts because such objects are not described in Roman texts and have not been found in Roman territory proper (i.e., senatorial provinces), only in the outlying provinces / colonies to the north:  Austria, Belgium, France, Germany, Hungary, Luxembourg, the Netherlands, Switzerland and the United Kingdom, but not in the Roman heartland in Italy.  They were mostly made in Gaul between the second and fourth centuries AD.  

Considering all the above, it would seem that the dodecahedra were a token of Celtic culture (religion / ritual) in northwest Europe during the Late Iron Age.

At their peak in the 3rd c. BC, the Celts expanded as far east as central Anatolia (modern-day Turkey), where they settled and established the region of Galatia (the Galatians of the New Testament).  They also reached the Carpathian Basin, the Danube region, Greece, the Balkans, and the Black Sea.

After its discovery in 2023, word of the NDD's discovery leaked to the public, and it was put on exhibition in a succession of local and regional museums during 2024 and up till today.  Of course, the news was quite sensational, and a flood of videos (dozens that I have seen) began to emerge.  Most of them were of poor quality.  They would get one or two experts to say a few words about how important the NDD was, but usually nothing substantial or reliable.  They were full of speculation, including the earlier claims that dodecahedra were for surveying and knitting gloves, etc., which they would splice together with stock footage of archeologists digging at the site and lots of imaginative drawings and historical illustrations that cannot realistically be linked to Gallo-Roman dodecahedra, NDD or otherwise. attendees at conferences, curators in storerooms, etc.), a few shots of reputable scientists discussing the results of their research, but mostly they had nothing directly to do with the NDD and shamelessly cribbed from each other.  They were pastiches of speculation and imagination.

Here's the best of this recent spate of videos inspired by the NDD that I have seen by now (probably at least two dozen):  

"Scientists Finally Solved the Roman Dodecahedron Mystery… And It Defies Human Origin" (beginning of February, 2026).  

Among others, it features Marcus Webb, lead archeometallurgist at Oxford University (7:10).  The narrator summarizes what Webb says (e.g., that the NDD is not Roman, but more importantly that chemical analysis points to the presence of cremated human bones in the context of calcium phosphate, amber, and rendered animal fat [a combination characteristic of funerary practices and necromantic rites in Iron Age Europe]), but we don't hear Webb himself speaking.

Yet even this relatively good documentary commits some howlers.  For instance, at 10:26, Isabelle Moreau, a paleographer specializing in medieval Latin, is said to have been examining a forgotten Latin ms in a Swiss monastic archives, Codex 134 Mistair Delore (supposedly dating to the 12th century), which has a description that eerily resembles the construction and possible use of a bronze object with twelve perforated sides….  Before you jump to any conclusions, be aware that the "Latin ms" Codex 134 Mistair Delore is actually an Old Armenian Bible translation Codex Etschmiadzin held in the Cambridge University Library.  I doubt that Dr. Isabelle Moreau is saying all those things about the bronze object with twelve perforated sides, and so forth, but rather that the videographer and narrator are attributing these words to her.

——–

This one is relatively decent too.

It's not worth my time or yours to mention the dozens of other videos on the dodecahedron that have popped up like mushrooms in recent months.  Sooner or later, someone or some responsible group of scholars are going to have to carry out a comprehensive study of the art, archeology, history, metallurgy, and other aspects of these enchanting objects.  

Meanwhile, I myself am not finished with dodecahedrons (including especially the NDD) — e.g., miniature dodecadrons strung on a necklace in Han period Southeast Asia and South China, and I will delve deeper into their association with Celtic expansion to the east in future posts.

Also, I will explore their relationship to the zodiac and the calendar (12 astronomical signs and 12 months); agriculture — when to plant; the cycle of 60 (called to my attention by Brian Pellar).  A Gallo-Roman dodecahedron found in London with 3 balls per vertex means that there were 60 of them (20 x 3).

I eagerly await a proper, full, scientific, scholarly report on the WDD.

 

Selected readings

• "Roman dodecahedron" — WP
• "Dallas Dodecahedron Daze Days" (1/28/26) — with many references to previous posts on dodecahedra
• "Amber in the east" (1/2/26) — with lengthy bibliography

———–

I have included the following article to show just how productive the idea of a dodecahedron is, how far it reaches.

"Acetylcholine-binding protein in the hemolymph of the planorbid snail Biomphalaria glabrata is a pentagonal dodecahedron (60 subunits)"
Michael Saur  1 , Vanessa Moeller, Katharina Kapetanopoulos, Sandra Braukmann, Wolfgang Gebauer, Stefan Tenzer, Jürgen Markl

     PMID: 22916297 PMCID: PMC3423370 DOI: 10.1371/journal.pone.0043685 

PubMed
PLoS One

National Library of Medicine

. 2012;7(8):e43685.
doi: 10.1371/journal.pone.0043685. Epub 2012 Aug 20. 

Abstract

Nicotinic acetylcholine receptors (nAChR) play important neurophysiological roles and are of considerable medical relevance. They have been studied extensively, greatly facilitated by the gastropod acetylcholine-binding proteins (AChBP) which represent soluble structural and functional homologues of the ligand-binding domain of nAChR. All these proteins are ring-like pentamers. Here we report that AChBP exists in the hemolymph of the planorbid snail Biomphalaria glabrata (vector of the schistosomiasis parasite) as a regular pentagonal dodecahedron, 22 nm in diameter (12 pentamers, 60 active sites). We sequenced and recombinantly expressed two ∼25 kDa polypeptides (BgAChBP1 and BgAChBP2) with a specific active site, N-glycan site and disulfide bridge variation. We also provide the exon/intron structures. Recombinant BgAChBP1 formed pentamers and dodecahedra, recombinant BgAChBP2 formed pentamers and probably disulfide-bridged di-pentamers, but not dodecahedra. Three-dimensional electron cryo-microscopy (3D-EM) yielded a 3D reconstruction of the dodecahedron with a resolution of 6 Å. Homology models of the pentamers docked to the 6 Å structure revealed opportunities for chemical bonding at the inter-pentamer interfaces. Definition of the ligand-binding pocket and the gating C-loop in the 6 Å structure suggests that 3D-EM might lead to the identification of functional states in the BgAChBP dodecahedron.

[Thanks to JP Mallory, Timothy Glover, and Lucas Christopoulos]

March 17, 2026 @ 9:09 am · Filed by Victor Mair under Language and archeology, Language and mathematics

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