Mosely Snowflake

The Mosely Snowflake is a three-dimensional cube fractal. Start with a cube, divide it into 3 x 3 x 3 smaller cubes, and then keep only a carefully chosen subset of them. Repeating that step builds a branching solid that looks part crystal, part snowflake.

Two common versions are usually shown. The heavier version keeps every small cube except the eight corner cubes, so it contains 19 cubes at each stage. The lighter version removes the center cube as well, leaving 18 cubes instead. That small difference changes the silhouette quite a bit, which is why it is interesting to switch between both versions.

It belongs to the same family of recursive cube fractals as the 2D Vicsek Fractal, the 3D Vicsek Fractal, and the Menger Sponge, just with its own denser rule for which cubes survive each step. The idea is also closely related to the Sierpinski Carpet: both begin with a regular grid and then keep only certain cells while the construction repeats at smaller and smaller scales.