The unfolded three-dimensional deltahedra are polyiamonds. This book offers step-by-step instructions explain how to fold polyiamonds into deltahedra with 12 faces or less.

I am a retired professor. I taught Combinatory Geometry in the department of Computer Science and Electric Engineering in Asia University, in Taiwan from 2003 through 2011. I was graduated MS from Michigan State University. East Lansing, Michigan in 1974 and DS from Washington University in St. Louis, Missouri in 1977. I constructed a toroidal deltahedra with 96 faces in 2005. I am interested in creating Taotie ( ) Models and counting deltahedra with 2n faces. I have spent two years to count and proof thirteen (13) deltahedra with 12 faces. Recently I found forty-seven (47) deltahedra with 14 faces and continue working on deltahedra with 16 faces.