A polyhedron is a geometric solid figure with polygonal faces. While there are some heraldic charges which might be described in this way – e.g., the die – the term here refers specifically to abstract geometric shapes, not otherwise defined, and which don’t appear to represent actual medieval objects. No examples of abstract polyhedra have been adduced in period armory; their use in Society armory is justified by the Renaissance knowledge of the Platonic solids, and the registrations to date have been drawn as such. The use of a polyhedron is deemed a step from period practice.
Alasdair O Cuinn bears: Per chevron Or and vert, two dragons combattant and an icosahedron counterchanged.