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Advanced Gemmology

Advanced Gemmology


The field of gemmology is consistently evolving, particularly in the various treatments, imitations, and methods of synthesis now available to improve and alter the appearance of a gemstone, or simply to deceive the unsuspecting buyer. 

This advanced online course will offer the learner a comprehensive and up-to-date knowledge on all the available methods of treatment, imitation, and synthesis and how to confidently identify them using standard and advanced gem testing. 


The course consists of 22 lessons and 2 tests –  together with 4 hours of online tutoring with one of our instructors. 

  1. Imitation stones
  2. Composite assembled stones
  3. Verneuil flame fusion method
  4. Czochralski pulling method
  5. Flux melt method
  6. Hydrothermal method
  7. Skull crucible method
  8. Zone melt method
  9. Horizontally oriented crystallisation method
  10. Synthesis of diamonds
  11. Sublimation method
  12. Modified Stober method
  13. Jadeite, lapis lazuli, turquoise, malachite and coral
  14. Less common lab-created gemstones
  15. Introduction to gemstone treatments and enhancements
  16. Heat treatment
  17. Surface and sub-surface diffusion
  18. Irradiation
  19. Fracture filling
  20. HPHT treatment
  21. Surface modifications
  22. Advanced gem testing techniques


For students who have completed the Basic Gemmology course and wish to know more or for experienced gemmologists who want to refresh their knowledge, this course is the perfect next step.


Upon the successful completion of this course you will receive a certificate of completion and course credits towards the Career Gemmologist Diploma and Coloured Gemstone Professional Diploma Programs.


  • Prerequisite needed: Basic Gemmology
  • This course is available for long distance learning. You can register at any time and study at your own pace. 
  • There are no time restrictions.
  • Price is £360 (Digital); the courses are also available in print at an additional cost. 
  • No basic gem testing equipment is included in the cost of this course.
  • Please note prices are given before tax. For UK residents VAT (20%) must be added.

For an overview of all available courses and study paths