Dr. Tahseenullah Khan is heading the Department of Earth and Environmental Sciences, Bahria University, Islamabad. He is a geologist by profession and has 39 years of industry, research and teaching experience. Dr Tahseenullah khan has been involved in many international projects including Geological Surveys of Japan and China, Naruto University of Education, Japan, University of Kagoshima, Japan and University of Grenoble France, Centre de Recherches Pétrographiques et Géochimiques (CRPG), France, and Amdel Mineral Laboratories, Australia. His major specialties are Geological mapping, mineral investigation, gemstone exploration, testing and mining. He has published more than 170 international and national research papers and extended abstracts, conference papers and book chapters. Many of his international papers are Q1 ranked. He published a book on “Gems and Gemmology in Pakistan” in 2010.