Direct time correspondence between crystal growth behavior and the thermal characteristics of the melt under destabilizing gradients was established by means of “time markers” which were introduced into the growing crystals and simultaneously registered on the continuous recording of the thermal behavior of the melt. Employing Te‐doped , it was found that as solidification progressed, the melt exhibited successively turbulent convection, oscillatory thermal instabilities, and, finally, thermal stability. During turbulent convection, the crystals underwent pronounced transient back‐melting and the average microscopic growth rate was found to be independent of, and about 20 times greater than, the average macroscopic growth rate; this microscopic growth rate was controlled by the convection characteristics of the melt and the thermal gradients in the solid. With the onset of oscillatory thermal instabilities, back‐melting became less pronounced and then ceased. In this region the average microscopic and macroscopic growth rates were equal and the crystals exhibited fluctuations in dopant concentration with a periodicity identical to that of the thermal oscillations in the melt. Finally, under stabilized thermal conditions, the microscopic and macroscopic growth rates were identical and no localized fluctuations in dopant concentration could be detected. The Rayleigh numbers of the melt during a growth experiment ranged from . In view of the fact that the vertical thermal gradient changed only by a factor of about two during the entire growth, the wide range of Rayleigh numbers was the result of the changes in melt height. In the turbulent convection region, the Rayleigh numbers ranged from about , in the oscillatory region from , and in the region of thermal stability from 103 to 0.