Ancient lime plasters belonging to Post-Ashokan, Sathavahana and Ikshvaku periods were analysed. It is observed that definite proportions of lime/silica are maintained in different periods and these were found in the range of 1.24 - 2.33; 0.69 and 0.67 - 3 57 for Post-Ashokan, Sathavahana Ikshvaku periods respectively. Relation between chemical analysis and periods of the plaster materials has been derived. The periods predicted agreed well with the data given by the Archaeologist. Analysis of lime plasters can aid in their conservation.