What is the phase transformation temperature anatase to rutile phase in tin dioxide(SnO2)?
Anatase and rutile phases form in $\ce{TiO2},$ the presence of cationic dopants or impurities significantly affect the transformation kinetics and phase stability [1].
It should be noted that anatase is metastable at all temperatures and pressures.

References


Hanaor, D. A. H.; Sorrell, C. C. Review of the Anatase to Rutile Phase Transformation. J Mater Sci 2011, 46 (4), 855–874. https://doi.org/10/ct79p8.