We report the results of our studies on the optical and thermal properties of binary mixture of compounds viz., abietic acid and ethylene glycol. The mixture shows very interesting co-existent biphasic region of aggregated columnar (C+I) and columnar (C) phases respectively at different concentrations of abietic acid sequentially when the specimen is cooled from its isotropic liquid phase. The temperature variations of optical anisotropy and optical textures have also been discussed.