Gyroelongated square bipyramid  

Type  Johnson J_{16}  J_{17}  J_{18} 
Faces  2.8 triangles 
Edges  24 
Vertices  10 
Vertex configuration  2(3^{4}) 8(3^{5}) 
Symmetry group  D_{4d} 
Dual  Square truncated trapezohedron 
Properties  convex, deltahedron 
In geometry, the gyroelongated square bipyramid is one of the Johnson solids (J_{17}). As the name suggests, it can be constructed by gyroelongating an octahedron by inserting a square antiprism between its congruent halves. It is a deltahedron.
The 92 Johnson solids were named and described by Norman Johnson in 1966.
Gyroelongated square dipyramid  

[[image:240pxGyroelongated square dipyramid]]  
Type  Johnson J_{16}  J_{17}  J_{18} 
Faces  2.8 triangles 
Edges  24 
Vertices  10 
Vertex configuration  2(3^{4}) 8(3^{5}) 
Symmetry group  D_{4d} 
Dual  Square truncated trapezohedron 
Properties  convex, deltahedron 
In geometry, the gyroelongated square dipyramid is one of the Johnson solids (J_{17}). As the name suggests, it can be constructed by gyroelongating an octahedron by inserting a square antiprism between its congruent halves. It is a deltahedron.
The 92 Johnson solids were named and described by Norman Johnson in 1966.
