Rhombicuboctahedron Star
Rhombicuboctahedron Star (also known as Moravian Star or Herrnhuter Star) with a base length of 20mm and spike angle of 5 degree.
There are different versions of the core, solid and hollowed, full or cut in half.
The model needs 18 of the square spikes and 8 of the triangular spikes. I prepared pre-hollowed versions with a wall thickness of 0.8 mm. You can also print the solid versions with no infill.
To hang it from a wire or chain, there are replacements for the square spike with either a big O-ring on top or a hole cut through the spike.
The star can be scaled to any size (using the solid versions). The models as provided result in a total span of 263 mm.
There is an LED version available at https://www.thingiverse.com/thing:4936670