Dodecahedron and the story of how India stood at the heart of a truly connected ancient world

In Corbridge, a Roman archaeological site near Hadrian’s Wall in Britain, a box believed to have belonged to a Roman soldier was discovered containing a set of artefacts. Among them were four objects that closely resembled items excavated in recent times at Pattanam, an archaeological site located in Kerala’s Ernakulam district in south India. This striking overlap has brought renewed attention to Pattanam’s role in the early historic Indian Ocean trade network, particularly as scholars seek to understand the far-reaching connections of the ancient world.

The 5 mm Pattanam gold dodecahedron

One of the most remarkable objects discovered at sites like Corbridge in Britain and Hepu in South China is the Roman dodecahedron. Interestingly, according to archaeologists, a gold artefact excavated from Pattanam also shares the dodecahedron shape, though it is smaller in size, made of gold, and crafted using a different technique.

The two-way passage of people, materials, animals, plants, technology, art, ideas and culture to and from Hepu Site in south China to the Corbridge site Atlantic via Pattanam at her peak phase 100 BCE to 300 BCE.

A dodecahedron is a three-dimensional geometric shape composed of 12 flat faces, each of which is a regular pentagon. In classical geometry, the dodecahedron is one of the five Platonic solids—highly symmetrical, convex polyhedral first described by the ancient Greeks. Of the five, the dodecahedron is the most complex.

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Roughly 120 such artefacts have been found across Europe, mostly in the northern provinces of the Roman Empire such as Gaul, Britain, and parts of Central Europe. Notably, none have been discovered in Italy, Spain, North Africa, or the eastern Mediterranean, making their distribution pattern unusual and their function the subject of ongoing debate among archaeologists.

In archaeological contexts, the term ‘Roman dodecahedron’ refers to a specific type of hollow, 12-faced object made of bronze or copper alloy, typically dating from the 2nd to 4th century CE. The function of Roman dodecahedra remains unknown. Scholars have proposed various theories, including use as surveying instruments, candlestick holders, knitting tools, astronomical devices, or ritual objects. The wide distribution and lack of written records have made them a subject of ongoing debate.

The dodecahedron found at Corbridge was made of copper alloy and recovered in a Roman military context. The example at Hepu, a coastal site in China’s Guangxi region that functioned as a Han dynasty port, was also made of copper alloy and excavated from a burial site. In contrast, the Pattanam dodecahedron, which surfaced during the Kerala Council for Historical Research (KCHR)’s excavations between 2007 and 2015, is made of gold, making it unique among all known specimens globally.

The Hepu dodecahedron

Archaeological context also differs significantly. The Pattanam dodecahedron appears to have been associated with a metallurgical workshop, suggesting it may have been manufactured or repurposed locally. Meanwhile, the Corbridge and Hepu pieces were found in secondary contexts—a military base and a burial site, respectively—indicating different uses or symbolic meanings in each location.

“This pattern resonates with what William Dalrymple describes as the Golden Road in his latest masterpiece,” said Dr. P.J. Cherian, former director of the KCHR, who led the pioneering team of historians, archaeologists, geologists, and scientific experts that launched Kerala’s first multidisciplinary excavation at Pattanam in 2007. “The presence of such objects across these far-flung regions—from Pattanam to Hepu to Corbridge—not only underscores the immense reach of ancient trade or exchange networks, but also suggests the layered cultural and symbolic meanings these artifacts carried across distant and diverse societies.”

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“The one found in Pattanam is really interesting because it looks like a local or regional version of the Roman dodecahedron. It’s made of gold, not bronze, and looks more like gold filigree work,” says Dr. Sharada Srinivasan archaeologist and a professor at the National Institute of Advanced Studies, Bangalore, specialising in the scientific study of art, archaeology, archaeometallurgy, and culture. “Each of the twelve pentagonal faces has a gold ring – fine gold wires shaped into loops. There’s clear evidence of a sophisticated goldsmithing technique- granulation may be, where tiny beads of gold are attached to a surface. Despite gold’s surface tension, it seems this was done using distinctive methods,” Dr. Srinivasan told The Federal.

“We also have findings from Karur with Roman motifs done using Indian craftsmanship. These pieces are all signs of deep trade and cultural exchange, especially through the Muziris port. So, this gold dodecahedron isn’t just Roman – it carries an Indic signature. It may have been made locally, either using Roman models or through collaboration with Roman artisans. We can’t say for sure what’s been lost or melted over time. It’s probably not a functional object like a tool – more likely a decorative item, maybe part of an earring or a pendant. This adds another layer to the story of Indo-Roman trade and how local craftsmanship evolved with it,” Sharada Srinivasan adds.

According to her, the filigree technique used in Pattanam dodecahedron shows a clear connection to Roman-style artistry, but instead of casting, it’s done with gold wirework.

A dodecahedron recently found in Britain

The Pattanam excavation has provided extensive evidence for a robust early historic trade network linking the Malabar coast to the Mediterranean, Red Sea, and Southeast Asia. Artefacts include Roman amphora shards, terra sigillata, Indian Rouletted Ware, semi-precious stone beads, glassware, copper coins bearing Chera symbols, and architectural remains such as brick wharves, ring wells, and a canoe. These findings are consistent with Pattanam’s proposed identification as Muziris, the ancient port referenced in the Periplus of the Erythraean Sea and Roman sources like Pliny the Elder.

The appearance of the dodecahedron at Pattanam adds a new dimension to these connections. Though the function of Roman dodecahedra remains uncertain—with theories ranging from tools for surveying or knitting to ritual or symbolic use—their presence across three sites separated by geography and culture raises important questions. The matching of artefacts between Corbridge and Pattanam, particularly within the same set of four objects, has prompted scholars to revisit assumptions about the scope and directionality of Roman-era exchange networks.

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“The find of Roman intaglios, jewellery in India and Roman bronze images from Kolhapur suggest that people obtain these objects as gifts and through trade,” opines Dr V Selvakumar, Head of the department of Maritime history and Maritime archaeology, Tamil University. “They definitely indicate the spread of cultural, material cultural traditions. Early Tamil literature speaks about Yavanas, Yavana warriors and Yavana lamps. The excavated material from the archaeological sites such as Arikamedu, Pattanam and other sites indicate the cultural connections across the Indian Ocean. People were accepting ideas, material culture and used them according to their own cultural context. They were also used as symbols of elites and traders,” Dr Selvakumar told The Federal.

“This also connects to the bigger picture of ancient Tamizhakam. Even in Keezhadi, Tamil Nadu, they’ve found motifs like golden flowers, adding weight to Sangam-era accounts of trade and prosperity. Sangam literature also mentions gold merchants, and there are also references to gold in places like Nilambur and Wayanad in Kerala. The findings from Keezhadi are important, though they seem to be from a time before the Roman contact. That’s clear when you look at the absence of Roman coins or other Roman objects there, and even the graffiti points to a different timeline. So even if Keezhadi itself is pre-Roman, it helps us understand the local culture that later interacted with the Roman world,” opines Dr. Sharada Srinivasan

However, the Hepu site in China, where another dodecahedron was found, has been dated to the Han dynasty period and was a known maritime trading port linked to Southeast Asia and the Indian subcontinent. The appearance of similar Roman-related objects there strengthens the argument that these artefacts did not move randomly but were part of wider exchange systems spanning from the Roman world through India to China.

This aligns with emerging scholarship on trans-Asiatic maritime trade routes, which emphasise the Indian Ocean as a conduit for goods, technologies, and cultural forms long before the colonial era. These routes connected Alexandria, Berenike, and Myos Hormos in the Roman world with ports like Muziris in India and Hepu in China. Pattanam, situated along the Periyar River with access to inland and maritime transport routes, fits well within this pattern.

The presence of the dodecahedron in these three distinct sites—military, funerary, and metallurgical—does not yet provide conclusive answers about its original function. However, the pattern does indicate that these objects may have acquired new meanings as they moved across space. Whether they were diplomatic gifts, trade curiosities, or items with practical or symbolic use, their geographic spread is a compelling indicator of the complexity and reach of ancient networks.

“There’s this fascinating paper on a dodecahedron found in Zurich—it suggests it might have been used as a die, but not in the way we know dice today,” says Rick Spurway, renowned documentary film maker who has worked expensively on Roman period gold mines. “In Roman times, they also had complex polyhedral dice, and this one, with its wear patterns and inscriptions, seems to have been part of some kind of astrological game or divination ritual. What’s wild is that it connects to a medieval Arabic text with 144 zodiac-based questions and dice-throw answers. It really makes you wonder—were all these dodecahedrons, even the ones with holes, ancient tools to read the future,” wonders Spurway

The Pattanam dodecahedron, with its gold composition and unique provenance, stands as a key piece of this larger puzzle—evidence not just of Roman contact with India, but of a layered and dynamic world where material culture flowed across empires, oceans, and civilisations.

“The devise definitely indicates the geometric knowledge of the Roman world and advancement in design and manufacturing. They could have been used as ornaments as they were used in China. It is possible that these artifacts, although were used as for specific purpose in the Roman World, they were used as ornaments in other parts of the world. Their function could be context specific. The Roman coins which had monetary value in Roma were used as ornaments in India,” says Dr. Selvakumar.

“It is unfortunate that the global archaeological and academic community has largely overlooked the significance of the Pattanam dodecahedron, especially considering it is the only known golden example of its kind. While the British and Chinese finds are routinely cited in discussions of Roman artefacts outside Europe, the Pattanam specimen remains relatively under-recognised, despite its uniqueness in both material and context,” feels Dr PJ Cherian who is serving as the managing trustee and director of PAMA (Paternal and Maternal Ancestry) the Institute for the Advancement of Transdisciplinary Archaeological Sciences.

What distinguished the Pattanam excavation was not just its multidisciplinary framework — integrating archaeology, archaeobotany, archaeo-metallurgy, sedimentology, and ethnoarchaeology — but also its pioneering community-oriented approach led by Dr. P J Cherian. This model, widely appreciated by both scholars and local stakeholders, created a participatory space where regional voices could engage meaningfully with broader archaeological narratives.

Today, the Pattanam initiative is regarded as a landmark in regional archaeology in India — a model that connects Kerala’s cultural memory with expansive transoceanic networks across the Red Sea, Mediterranean, and South China Sea, particularly during the peak of the Indo-Roman trade between 300 BCE and 300 CE.

Further research is ongoing. KCHR’s post-excavation studies include analysis of metal artefacts, stone bead production, and ceramic typologies, including Indian Rouletted Ware. Parallel efforts by archaeologists and historians to reassess Roman artefacts found in India, China, and Britain may help clarify how such items moved across regions, and how they were used or understood in different cultural settings.