Watch The Webinar

Please find below the HD-quality recorded webinar by Tanja Sadow.


– 0:00 – 4:57: Overview of the classification, identification of species and varieties of gems
– 4:57 – 20:02: The first C: Colour
– 21:04 – 24:04: 4-minute Interlude: Alex’s introduction to JDMIS Gem and Trade Secrets Certificate
– 24:03 – 27:52: The second C: Clarity
– 27:55 – 37:47: Clarity in the case of diamonds
– 37:48 – 39:02: The third C: Carat Weight
– 39:03 – 46:42: The fourth C: Cutting & Style
– 49:07 – 58:12: The Syllabus of JDMIS’ flagship Gemmology Certification Course

About the Speaker

Tanja Sadow

Tanja is an award-winning jewellery designer and gemmologist with more than 4 decades of experience educating the jewellery industry across 4 continents. As Dean and founder of JDMIS, Tanja trains teams from top jewellery brands and works with aspiring artisans to help them achieve brilliance in their careers.


The Jewellery Design & Management International School is the leading specialised jewellery institution in Singapore and the region. JDMIS offers internationally recognized professional certifications, diplomas and advanced diplomas in jewellery design, fabrication and business

Years of Operation
Certified graduates
Enable Notifications OK No thanks