[en] It is shown that under crystallization of strongly dilluted macroscopic binary solid solutions in the region of weak supercoolings in each layer of the transition region only one spontaneous thermal equilibrium fluctuation is practically possible as a result of which particles concentration in solid state takes the mean value of concentration calculated for the case of proper binary microsystems. The kinetics of crystals growth of strongly dilluted macroscopic binary solid solutions (particular form of binary metallic macrosystems) in the region of weak supercoolings of the binary melt-crystal system is described with normal law (ν*=K*ΔT) caused by the action of mechanism of spontaneous fluctuations with limited spectrum of variation of solid particle concentrations in the layers of transitional two-phase zone. The expression for the kinetic coefficient of normal crystallization law in the case of strongly dilluted macroscopic binary solid solutions. Theoretical estimates of medium crystallization rate of a series of strongly dilluted binary solid solutions in the region of weak supercoolings of the melt-crystal system are in good agreement with the available experimental data