Combined experimental and numerical tools are used to analyze the effect of convective and radiative heat transport, faceting phenomena, and the optical thickness of the Bi4Ge3O12 (BGO) crystal on the measurement and calculation of melt/crystal interface kinetics during the axial heat flux close to the phase interface growth of BGO single crystals. Results show that, in the general case, accurate determination of growth kinetic relations requires the application of models which account for all of the above phenomena (radiative and convective heat transport, faceting phenomena, etc.). Failure to take these into account may result not only in quantitative errors, but also even in qualitatively wrong determination of interfacial kinetic mechanisms. (C) 2004 Elsevier B.V. All rights reserved.