Mixed single crystals of calcium strontium tartrate (CST) of high optical quality and morphological perfection have been grown from light irradiated sodium meta silicate gel medium at ambient temperature. The results obtained on characterization of CST crystals using EDX, chemical analysis, X-ray diffraction and infra-red spectral techniques are reported. A thermogravimetric study is carried out in order to study the kinetic parameters and associated mechanism of dehydration process. The two dimensional diffusion mechanism is suggested for the solid state nonisothermal dehydration step in CST crystals. The CST crystals turn out to be a tetrahydrate and the crystals are thermally unstable. The chemical composition was thus established as Ca 0 . 5 Sr 0 . 5 C 4 H 4 O 6 4H 2 O.