I copyrighted the design for these dice in 1995 as part of my International Bone Rollers Guild project. At last, I've finally been able to produce and distribute them through Shapeways! This is a truly unique design for a D12 die, based on my original hand-carved wooden models. I've been using them for years in my role-playing worlds, and now you can have one, too! These dice are hollow, and just under 1-1/2 inches in diameter.
The shape of this die is one of a group of polyhedra known as the Catalan Solids, which are geometric duals to the Archimedean Solids. This shape, known as the Triakis Tetrahedron, is dual to the Truncated Tetrahedron. Unlike other dice of its shape, this copyrighted design actually rolls numbers from 1 to 12. And, just as an ordinary 6-sided die has its pips arranged so that opposite sides add up to 7, this die has its numbers arranged so that opposite sides add up to 13.