Bicone

A bicone or dicone (bi- comes from Latin, di- from Greek) is the three-dimensional surface of revolution of a rhombus around one of its axes of symmetry. Equivalently, a bicone is the surface created by joining two congruent right circular cones base-to-base.

Geometry

For a circular bicone with radius R and height center-to-top H, the formula for volume becomes

V = \frac{2}{3} \pi R^2 H.

For a right circular cone, the surface area is

SA =2\pi R S\,

where

S = \sqrt{R^2 + H^2}

A bicone can be seen as a polyhedral limiting case of an n-gonal bipyramid where n approaches infinity. It can also be seen as a dual of a cylinder as an infinite-side prism.^[1]