Close-packing of equal spheres
（重定向自Close Packing）
![Illustration of the close-packing of equal spheres in both hcp (left) and fcc (right) lattices](/Images/godic/202501/05/Close_packing_box.svg2122.png")
![fcc arrangement seen on 4-fold axis direction](/Images/godic/202501/05/Square_circle_grid_spheres2122.png")
![](/Images/godic/202501/05/Cuboctahedron_B2_planes2122.png")
![](/Images/godic/202501/05/Cuboctahedron_3_planes2122.png")
In geometry, close-packing of equal spheres is a dense arrangement of congruent spheres in an infinite, regular arrangement (or lattice). Carl Friedrich Gauss proved that the highest average density – that is, the greatest fraction of space occupied by spheres – that can be achieved by a lattice packing is