Roman Empire Dodecahedron Mystery

The first of many dodecahedrons was unearthed almost three centuries ago, and we still don't know what they were for. Maybe you can solve the mystery?

Picture shows: Two Roman dodecahedrons (left and center) and the only known example of an icosahedron (with 20 sides, right), all on display in the Rheinisches Landesmuseum in Bonn, Germany.

The story goes like this: In 1739, a strange, twelve-sided hollow object from ancient Roman times was discovered in England. Since then, more than a hundred dodecahedrons have been unearthed, but their purpose remains unknown. The only thing we know for sure is where they were found, which points to a Gallo-Roman connection.

One of the strongest clues we have is this map, which tells us that they were particularly popular in one corner of the Roman Empire: northern Gaul and Roman Germany.

So, what do we know? Roman dodecahedrons - or more properly called Gallo-Roman dodecahedrons - are twelve sided hollow objects, each side pentagonal in shape and almost always contain a hole. The outer edges generally feature rounded protrusions.

Most of the objects are made from bronze, but some are in stone and don't have holes or knobs. The dodecahedrons are often fist-sized yet can vary in height from 4 to 11 cm (about 1.5 to 4.5 in). The size of the holes also varies, from 6 to 40 mm (0.2 to 1.5 in). Two opposing holes typically are of differing sizes.

Objects of this type were unknown until the first one was found in 1739 in Hertfordshire, England. In all, 116 have been dug up from sites as far apart as northern England and Hungary. But most have been found in Gaul, particularly in the Rhine basin, in what is now Switzerland, eastern France, southern Germany, and the Low Countries. Some were found in coin hoards, indicating their owners considered them valuable. Most can be dated to the 2nd and 3rd century AD.

For now, and perhaps forever, the mystery of the Roman dodecahedrons remains unsolved.


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