<P> The bipyramid whose six faces are all equilateral triangles is one of the Johnson solids, (J). A Johnson solid is one of 92 strictly convex polyhedra that have regular faces but are not uniform (that is, they are not Platonic solids, Archimedean solids, prisms or antiprisms). They were named by Norman Johnson, who first listed these polyhedra in 1966 . As a Johnson solid with all faces equilateral triangles, it is also a deltahedron . </P> <P> The dual polyhedron of the triangular bipyramid is the triangular prism, with five faces: two parallel equilateral triangles linked by a chain of three rectangles . Although the triangular prism has a form that is a uniform polyhedron (with square faces), the dual of the Johnson solid form of the bipyramid has rectangular rather than square faces, and is not uniform . </P> <Table> <Tr> <Th> Dual triangular bipyramid </Th> <Th> Net of dual </Th> </Tr> <Tr> <Td> </Td> <Td> </Td> </Tr> </Table> <Tr> <Th> Dual triangular bipyramid </Th> <Th> Net of dual </Th> </Tr>

Shape with 6 vertices 9 edges and 5 faces