Branko Deljanin is President and Head Gemologist at CGL and Director of Gemmological Research Industries Inc, Vancouver (Canada). He is a research gemologist with experience in advanced testing of diamonds and gemstones. He is an expert in identification of natural, treated and synthetic diamonds and gems for subsequent certification and works with lab instruments to determine origin of color for colored diamonds and gems, and provenance of pink diamonds.

Branko is an instructor of Intermediate-Advanced Gemology programs he is offering in 20 countries on 4 continents.

He has been a regular contributor to trade and gemological magazines and presented reports at several prestigious research and gemological Conferences, including Mediterranean Gemmological and Jewelry Conference that he co-founded in 2015. His latest book (2021) is on DIAMONDS Natural, Treated and Laboratory-grown.