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. 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. A bicone has circular symmetry and orthogonal bilateral symmetry. For a circular bicone with radius R and height center-to-top H, the formula for volume becomes