ANTIPRISMS
Antiprisms comprise a family of semiregular polyhedra;
the ends (top & bottom)
of the antiprism are identical regular
N-polygons,
with corresponding sides offset by half a face
and connected by 2N triangles.
In general the end-polygons can be convex or can
be stars. Examples:
Convex antiprisms
Pentagonal antiprism,
hexagonal antiprism,
heptagonal antiprism:
etc.
Nonconvex antiprisms
Pentagrammatic antiprism:
.............
Heptagrammatic (7:3) antiprism:
.............
etc.