The present work aims at qualitative investigation of cesium content present in a glass. A glass comprising (wt%) Cs2O(30)-SiO2(35)-Na2O(7)-SnO2(4)-Z nO(24) was prepared in a conventional heating furnace. A novel method was developed adopting gravimetric analysis of cesium content in the glass samples using Dragendorff's reagent, leading to formation of Cs3Bi2I9 crystal (salt). Experimental methods were examined to purify the salt. Qualitative analysis was performed on Cs3Bi2I9 crystal with FESEM-EDX and XRD. Up to & SIM;93% pure Cs3Bi2I9 could be synthesized. Quantitative studies were performed with standard cesium solution prepared with Cs2CO3 with varying compositions of cesium within 1000 to 3000 ppm. Weight of salt produced was concluded to be strongly related to the cesium content present in the glass solution