Ancient3DCraftsRoman Dodecahedron

Guide

Roman Dodecahedron Size, Weight and Materials

Key points

  • 4–11 cm across, holes 6–40 mm.[W]
  • 35 g to 1 kg.[W]
  • Cast in copper alloy by the lost-wax technique; the knobs were usually soldered on.[W]
Two Roman dodecahedra of different sizes from Tongeren and Bassenge
Two dodecahedra of different sizes, from Tongeren and Bassenge. Photo: Kleon3, CC BY-SA 4.0, via Wikimedia Commons (resized).

Size and weight range

ExampleSizeWeight
All known examples4–11 cm35 g – 1 kg[W]
Norton Disney (2023)About 8 cm245 g[LCC]
Kortessem fragment (2023)Just over 5 cm originally—[LS]
Our replica (Brian Campbell model)10.05 cmJust under 600 g

How they were made

They were cast using the lost-wax technique. The outsides are well finished and were probably polished, while the interiors were left unfinished. The corner balls are not perfectly regular, suggesting they were made without a mould, and are generally soldered on, though the Carmarthen example at the Society of Antiquaries of London was cast in one piece. One London find has clusters of three balls at each corner.[W]

The holes

Each face has a circular hole of a different diameter, connecting to the hollow centre, commonly framed by two or three concentric circles.[W]

FAQ

How big is a Roman dodecahedron?

Between 4 and 11 cm across.

What are they made of?

Copper alloy (bronze), cast by the lost-wax method.

How heavy are they?

From 35 g to 1 kg.

Sources

  1. [W] Wikipedia, “Roman dodecahedron” (accessed Oct 2026)
  2. [LCC] Lincolnshire County Council, “Mysterious Roman dodecahedron found in Norton Disney to go on display in Lincolnshire for the first time”
  3. [LS] T. Metcalfe, “Mysterious 12-sided Roman object found in Belgium may have been used for magical rituals,” Live Science, 26 Jan 2023