I understand that, and thank you for answering. I can reveal that the underlying question I have is if this phenomenon, principle, possibly also applies to deeper crust and mantle of Earth. Usually one assumes and reads that "heavier matter sinks down", but here we have a physical phenomenon where the heavier/bigger particles stays on top while lighter/smaller particles sinks down.
The answer you gave is a geometric explanation (=in perfect spherical spaces, in a collection of 1-radius spheres - let´s say in a bowl with 1-radius spheres - then a sphere that has the radius of 0,1547... exactly 1/(3+squareroot(12))... can move freely/can´t be blocked by the bigger spheres) and I am wondering if the same effect happens deeper in the Earth?
I realize a lot of other effects come into play in the depth of Earth, chemistry, surface tension, temperature, phase shifts - when atoms e g become gaseous before other atoms etc, but this geometric relation also possibly plays a role - or does it?
As you see the question becomes complicated and I asked the original question to see if I quickly could find keys to where to look.