A cuboctahedron is defined as which type of crystal?

• A. A crystal with both octahedral and cubic faces
• B. A crystal with only hexagonal faces
• C. A molecule formation in graphite
• D. A random arrangement of cubic units

Answer: (A)

A cuboctahedron has both octahedral and cubic faces. It is built from a mix of triangular faces (like those on an octahedron) and square faces (like those on a cube), specifically eight triangles and six squares. This blend of face types is what defines its shape and places it among Archimedean solids, often described as a truncation that yields both cube- and octahedron-like faces. The other options describe hexagonal faces, graphite chemistry, or a random arrangement of cubes, none of which capture the mixed-square-and-triangle face structure of a cuboctahedron.