We study the collective sedimentation of cube-shaped particles in the Stokes regime using direct numerical simulations based on the smooth profile method. The particles, constructed as rigid assemblies of $3\times 3\times 3$ spherical beads, settle in a Newtonian fluid at Reynolds number $\mathrm{Re}=0.1$ over volume fractions $0.001\le \varphi \le 0.08$. Although orientation-dependent hydrodynamic forces at the single-particle level, the suspension recovers the classical Stokesian scaling laws traditionally associated with spherical particles. The radial distribution function exhibits a single dominant peak that grows monotonically with $\varphi$, indicating isotropic microstructural organization and progressive clustering. Orientation statistics show random alignment in dilute suspensions and a transition toward preferential alignment at ${45}^{\circ }$ with respect to gravity as concentration increases. The mean settling velocity follows the Richardson-Zaki law with exponent $n\simeq 6$, velocity fluctuations scale as ${\varphi }^{1/2}$, and relaxation timescale as ${\varphi }^{-1/2}$. Self-diffusion coefficients increase weakly with volume fraction and asymptotically approach the ${\varphi }^{1/2}$ scaling characteristic of spherical suspensions. These results demonstrate that geometric symmetry, rather than sphericity alone, governs the emergence of sphere-like collective sedimentation behavior in nonspherical particle suspensions under creeping-flow conditions.

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• Boundary layers
• Fluid-particle interactions
• Interparticle interactions
• Laminar flows
• Low Reynolds number flows
• Multiphase flows
• Particle interactions
• Sediment transport
• Stokesian dynamics
• Colloids
• Rheological properties
• Direct numerical simulations
• Eulerian flow field
• Navier-Stokes equation