Decagonal antiditetragoltriate

The decagonal antiditetragoltriate or daddet is a convex isogonal polychoron and the eighth member of the antiditetragoltriate family. It consists of 20 decagonal prisms, 200 rectangular pyramids, and 200 tetragonal disphenoids of two kinds. 2 decagonal prisms, 4 tetragonal disphenoids, and 5 rectangular pyramids join at ecah vertex. However, it cannot be made scaliform.

It can be formed as the convex hull of 2 oppositely oriented semi-uniform decagonal duoprisms where the larger decagon is more than $$\sqrt{\frac{10-2\sqrt5}{5}}$$ times the edge length of the smaller one.