Actually, this shape is a near-miss, two of the leafs are not in contact. The gap is small though.
The rhomb used there is made of two equilateral triangles with a diagonal ratio of sqrt(3) = 1.732... The true shape would use golden rhomb with a ratio of 1.618...
There is a whole family of models that can be made using acute golden rhomb and obtuse golden rhomb.
See my blog post here
https://asliceofcuriosity.fr/blog/posts/geometry11.htmlIn the hope that someday GeomagWorld SA makes golden rhomb panels.
In the meantime, here are the 3D models for lazarosmotsanos pictures.