TypeOnline Course
Student Enrolled179
Certificate70% of quiz marks
(4 ratings)

IIJA Student Registrations have been transferred to the International School of Gemology

Effective today December 23, we have formally withdrawn from our status as a 501(c)3 Non-Profit, and returned to our original structure and location at the International School of Gemology. All courses on this IIJA website are now closed, and all student registrations and files have been transferred to the ISG location. Your Username and Password should be active and waiting for you. Student registrations, course history, and student files have been migrated. Please contact us for any questions or if we can help with any issues.

Robert James FGA, GG
President, International School of Gemology


IIJA Colored Gemstones Course

The course includes 17 lessons that will take you through the entire process of gemstone formation including a video field trip to a topaz producing pegmatite dike. We will look at 60 of the most often seen colored gemstones and learn about their formation, properties and how to identify them in preparation for our Gemology Tools and Techniques course. Gem Equipment is not required to complete this self-study course. Those wishing to complete the IIJA RG or RGA program will get credit for this course.

Please read the IIJA Student Registration Contract before beginning this course. By your registration and payment for this course, you are agreeing to the IIJA Student Registration Contract.


Course Number: IIJA102
Program: Individual Course, Registered Gemologist and Registered Gemologist Appraiser
Certificate of Completion: Yes

Subjects Covered in this Course:

  • Getting Started
  • Why Gemstones Have Color
  • Gemstone Properties 1
  • Gemstone Properties 2
  • Crystal Systems
  • Gemstones A – E
  • Gemstones F – M
  • Gemstones O – S
  • Gemstones T – Z
  • Isomorphous Replacement Series
  • Gemstone Phenomena 1
  • Gemstone Phenomena 2
  • Created and Treated Introduction
  • Diffusion
  • Gemstone Color Grading
  • Gemstone Cut Grading
  • Gemstone Clarity Grading
  • Final Exam

Completion of this course will apply toward earning your IIJA Registered Gemologist Appraiser or IIJA Registered Gemologist Diplomas.

How to Begin:

  • When you pay for this course using any credit card or your account on PayPal you will be able to start immediately.
  • SSL Secure Payments can be made either through Stripe Payments for credit cards, or PayPal using any credit card or PayPal card using the PayPal payment system. You do not need to have a PayPal Account to use your credit card through PayPal. The Stripe Payment system is for general credit card use. Please follow these steps carefully.:
    1. Click on the BUY NOW button on the upper right side of this page.
    2. The payment gateway will take you through the PayPal or the Stripe payment systems. Both are SSL Secure payment systems. PayPal uses either a PayPal account or you can use other credit cards with PayPal without having a PayPal Account. Stripe is used for Mastercard and Visa and other cards also.
    3. Once you receive payment confirmation you will be brought back to your course to begin or to the SchoolofGemology.com website. Either way, go to the course home page to begin. You can also access the course page through your Profile Page.
    4. Once you have returned to the course home page click the Start the Course button to begin.
    5. Once complete you can print your temporary certificate of completion.  Your IIJA Certificate of Completion will be sent from the IIJA office. Please allow up to 4 weeks to receive your certificate if you are outside the United States.
Section 1Getting Started
Section 2Why Gemstones Have Color
Section 3 Gemstone Properties
Section 4 Optic Character / Sign
Section 5The Crystal Systems
Section 6Individual Gemstone Study A - E
Section 7Individual Gemstone Study F - M
Section 8Individual Gemstone Study O - S
Section 9Individual Gemstone Study T - Z
Section 10Isomorphous Replacement Series
Section 11Gemstone Phenomena, Part 1
Section 12Gemstone Phenomena, Part 2
Section 13Created-Treated-Imitation Gemstones
Section 14Bulk Diffusion Process
Section 15Evaluation of Color
Section 16Evaluation of Gemstone Cut
Section 17Evaluating Gemstone Clarity
Final Quiz