Guide

The Roman Icosahedron and Other Related Objects

Key points

  • A Roman icosahedron from Arloff, Germany, long misclassified as a dodecahedron, is in the Rheinisches Landesmuseum Bonn.[W]
  • A solid silver dodecahedron with zodiac names was found in Geneva in 1982.[W]
  • Smaller gold dodecahedra are known from Southeast Asia, e.g. Óc Eo, Vietnam.[W]
Roman dodecahedra and the Arloff icosahedron at the Rheinisches Landesmuseum Bonn
Two dodecahedra and an icosahedron (3rd century AD), Rheinisches Landesmuseum Bonn. Photo: Kleon3, CC BY-SA 4.0, via Wikimedia Commons (resized).

The Arloff icosahedron

Like the dodecahedra it is hollow bronze with spheres on each corner. Only two opposite faces have holes, and three knobs around one face are larger, giving it an obvious orientation: on those three “feet”, the larger hole is at the top.[W]

Other relatives

ObjectWhereNotes
Arloff icosahedronGermany20 faces, holes in two faces[W]
Saint-Trivier-de-Courtes object (2009)FranceSpherical, triangular and pentagonal holes[W]
Geneva dodecahedron (1982)SwitzerlandSolid silver; zodiac sign names on the faces[W]
Óc Eo gold dodecahedraVietnamSmaller, gold; seen as Mediterranean trade influence[W]

FAQ

Is there a Roman icosahedron?

Yes, from Arloff in Germany, now in the Rheinisches Landesmuseum Bonn.

Have dodecahedra been found outside Europe?

Smaller gold dodecahedra are known from Southeast Asia, including Óc Eo in Vietnam.

Sources

  1. [W] Wikipedia, “Roman dodecahedron” (accessed Oct 2026)