The least symmetrical cubic forms as described by AEH Tutton: a Pentagonal Icositetrahedron, a Tetrahedral pentagonal Dodecahedra, both with left and right forms, and a related mineral - Cuprite. See "Crystallography and Practical Crystal Measurement", AEH Tutton, Macmillan and Co. Ltd, London, 1911, Chapter XI, p. 157. and also Figures 107, 109, and 111. https://archive.org/details/crystallographyp00tuttuoft Tutton's "Cubic System" chapter starts with the forms with most symmetry elements and ends with those with the fewest elements. These models together with things 863463, 861532, 859902, and 858220, add models to go with Tutton's figures as an aid to understanding cubic forms. Tutton writes clearly without using advanced mathematics.