New correlations have been developed to estimate the steady-state free-fall conditions of isolated, nonspherical, isometric particles moving in Newtonian fluids. The proposed relationships cover the Stokes, the Newton, and the transitional flow regions. Their explicit forms enable the direct computation of the particle size corresponding to a chosen terminal velocity and the straightforward calculation of the terminal velocity of a given nonspherical particle. The terminal velocities of crushed particles of limestone and lime have been measured and compared to the values predicted by the proposed formulas.