Hexagonal trapezohedron

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Hexagonal trapezohedron
face-transitive

In

dual polyhedra to the antiprisms. It has twelve faces which are congruent kites. It can be described by the Conway notation dA6
.

It is an

Symmetry

The symmetry a hexagonal trapezohedron is D6d of order 24. The rotation group is D6 of order 12.

Variations

One degree of freedom within D6 symmetry changes the kites into congruent quadrilaterals with 3 edges lengths. In the limit, one edge of each quadrilateral goes to zero length, and these become bipyramids.

Beta-quartz is the only common mineral with this crystal system.[4]

If the kites surrounding the two peaks are of different shapes, it can only have C6v symmetry, order 12. These can be called unequal trapezohedra. The dual is an unequal antiprism, with the top and bottom polygons of different radii. If it twisted and unequal its symmetry is reduced to cyclic symmetry, C6 symmetry, order 6.

Example variations
Type Twisted trapezohedra (isohedral) Unequal trapezohedra Unequal and twisted
Symmetry D6, (662), [6,2]+, order 12 C6v, (*66), [6], order 12 C6, (66), [6]+, order 6
Image
(n=6)
Net

Spherical tiling

The hexagonal trapezohedron also exists as a

spherical tiling
, with 2 vertices on the poles, and alternating vertices equally spaced above and below the equator.

Related polyhedra

Uniform hexagonal dihedral spherical polyhedra
[6,2]
, (*622)
[6,2]+, (622) [6,2+], (2*3)
{6,2} t{6,2} r{6,2} t{2,6} {2,6} rr{6,2} tr{6,2} sr{6,2} s{2,6}
Duals to uniforms
V62 V122 V62 V4.4.6 V26 V4.4.6 V4.4.12 V3.3.3.6 V3.3.3.3
Family of n-gonal trapezohedra
Trapezohedron name Digonal trapezohedron
(Tetrahedron)
Trigonal trapezohedron Tetragonal trapezohedron Pentagonal trapezohedron Hexagonal trapezohedron
Heptagonal trapezohedron
Octagonal trapezohedron
Decagonal trapezohedron
Dodecagonal trapezohedron
...
Apeirogonal trapezohedron
Polyhedron image ...
Spherical tiling
image
Plane tiling
image
Face configuration
V2.3.3.3 V3.3.3.3 V4.3.3.3 V5.3.3.3 V6.3.3.3 V7.3.3.3 V8.3.3.3 V10.3.3.3 V12.3.3.3 ... V∞.3.3.3

References

External links