Currently, high quality ruby and sapphire deposits of Viet Nam are found in Yen Bai (Luc Yen district) and Nghe An (Quy Chau and Quy Hop) provinces. Dark color sapphire with large reserves is being extracted in the Central Highland provinces such as Gia Lai, Dak Lak and Lam Dong. Sapphire is also extracted in Dong Nai and Binh Thuan provinces. Besides, ruby and sapphire have lower reserves and quality are also extracted in Quang Nam. By studying and comparing ruby and sapphire from different deposits in terms of gemological and chemical characteristics, one can identify typical characteristics of each deposit and differentiate their geographical origins, sapphire from Central Highland, Southern provinces and from Quang Nam provinces have low gem quality in comparison to the samples from Yen Bai and Nghe An. The averaged amount of Fe in Central Highland sapphire is considerably higher than all other areas. The authors can separate between ruby from Nghe An and ruby from Yen Bai by the ratios of coloring elements Fe2O3/Cr2O3 and TiO2/Cr2O3. Even in some cases, ruby from different deposits in Yen Bai can be distinguished by the concentration of Cr and Fe.