https://gemology.pro/course/introduction-to-gemology/
The Introduction to Gemology course has been designed explicitly as a foundation study of gemology for those just starting their careers in gemstones. This foundation course includes information that is taken directly from the ISG Registered Gemologist Appraiser program and more. It is designed for those without gemology experience to get a foundation knowledge in gemology to serve their future learning needs.
This program consists of a 9-lesson course in gem and mineral formation, how gemstones are mined, how gemstone crystals grow, basics of gem identification, a review of over 67 of the most often seen gemstones, and a full section on Careers in Gemology.