The man who can tell diamonds apart (BBC Documentary)

John King, Chief Quality Officer (Gemological Institute of America)

Director/Producer/Editor: Yannis Zafeiriou (yanzaf.com)

Executive Producer: BBC WORKLIFE

Supervising Producers: Anna Bressanin & Kieran Nash

Producer: Bernadette Young

Special Thanks
Gemological Institute of America
Nellie Barnett