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Archimedean Solids · 3D

Truncated Cube

3.8.8 · t{4,3}

Truncated Cube, drawn as a glowing line figure

Slice the eight corners off a cube until every square becomes a regular octagon. Eight small triangles appear where the corners were.

Vertices
24
Edges
36
Triangles
8
Octagons
6

Open in SacredForm

Turn it in your hands, strike it to hear the chord of its edges, slice it with a plane.

Facts

  • For regular octagons the cut runs 1 − 1/√2 ≈ 0.293 of the way along each edge.
  • Across its octagons it measures 1 + √2 edges: the silver ratio, which the octagon holds as the pentagon holds φ.
  • Every corner joins one triangle and two octagons (3.8.8).
  • Its dual, the triakis octahedron, is an octahedron with a low pyramid raised on every face.

History and meaning

Renaissance artists drew the cut solids as exercises in perspective. Wenzel Jamnitzer’s Perspectiva Corporum Regularium (1568) is a whole book of them, turned, hollowed and stellated.

Across the dimensions

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