Professional Certifications

Professional Gemologist Certification Course

  • Intermediate
  • 6 UNITS
  • 95 LESSONS

The International Gem Society (IGS) was one of the first online schools of gemology to serve a global audience. Our goal is to provide a flexible and affordable education in gemology. IGS's founder, Donald Clark, CSM IMG, created a robust testing process to ensure that those with IGS certification would stand out in the crowd. IGS continues to use the testing process created by Donald Clark to ensure continuity and rigor.

Start this course for $400 (plus the cost of Pro Membership)

About this course

The International Gem Society (IGS) was one of the first online schools of gemology to serve a global audience. Our goal is to provide a flexible and affordable education in gemology. IGS's founder, Donald Clark, CSM IMG, created a robust testing process to ensure that those with IGS certification would stand out in the crowd. IGS continues to use the testing process created by Donald Clark to ensure continuity and rigor.

  • Intermediate
  • 6 UNITS
  • 95 LESSONS

Who is this course for?

  • Professional Gemologists: Sharpen your skills.
  • Hobbyists: Enhance your knowledge.
  • Aspiring Gem Professionals: Learn key knowledge and skills to pursue your passion

What this course offers

  • Learn basic gemology.
  • Understand gem properties.
  • Use gemology tools.
  • Identify gemstones.

Why take this course?

Accelerate your path towards a professional gemology career by becoming an IGS-certified Professional Gemologist.

Course Roadmap

Read the Lessons

Written Exams

Practical Exam

Earn Certificate

Units & Lessons

Frequently Asked Questions

What tools I will need?
ToolVendorsEstimated Price
Microscope GEMORO® Elite 1030 Microscope $430.00
Loupe 10X Gesswein® 20.5mm Hex Triplet Loupes - Black $21.95
Tweezers D-Master Soft Tip Tweezers $29.95
Scale GEMORO® Platinum XP500 Scale (Capacity: 500g) $29.95
Spectroscope Handheld Durable Small Diffraction Spectroscope 55mm $26.90
Refractometer Ade Advanced Optics GL500 Gem Refractometer $99.99
Calipers 4" Electronic Digital Pocket Caliper $36.05
Will I be assigned an instructor for the course?

The course is self-study. This means that all of the material is on our website, and the burden is on the student to follow the Syllabus to learn the material.

The benefit of this approach is that each student can learn at his or her own pace, and on his or her own schedule. Students can take as long as they want to complete each exam in the certification process to ensure familiarity and understanding of the material.

Won’t the self-study model be difficult if I’m a beginner?

For beginners we recommend following our structured Syllabus, however you may study the material in any order that suits you.

What is required to pass?

In order to pass the certification process the student must:

  1. Pass three 100-question written exams with a score of 87% or better. The student may retake the exams an unlimited number of times until they pass each one.
  2. Thereafter, the student must also pass a practical exam which requires identifying and grading 15 gemstones. We will mail you the gemstones, which will be common to the trade and include natural, enhanced, synthetic, and assembled stones. Deductions will be made for errors, and the applicant must score 93% or better to pass.
  3. When the written and practical tests have been completed with passing scores, the IGS-Certified Professional Gemologist certificate will be awarded.
How are the tests administered?

All examinations are administered via online test-taking software accessed via your password-protected account on the IGS website.

Can I see a sample of the test questions?

Sure! We’ve posted the following sample gemology questions from the actual IGS certification exam. This should give you a sense of the scope of the tests. Questions cover gemstone formation, properties of specific gems, gem identification, and testing, as well as faceting, grading, and appraising.

How long should it take me to complete the course?

The course is quite involved. This is not a casually created e-course, but rather a very comprehensive overview of some challenging material. We’ve been improving the material for over 20 years. Some members with previous gemology or geology experience have completed the course in as little as three months, others are still chipping away at it after two years. It really depends on your level of interest, motivation, and time commitment. The average time to completion is probably around a year, studying part-time.

Can I get a refund if I am not satisfied?

Please note that certification costs are non-refundable. A $50 refund is given if you choose to return the stones used for the practical test. (You may keep the stones instead, if you wish.)

How does the IGS course compare with those offered by the GIA or similar organizations?

The GIA is an excellent organization. Their Graduate Gemologist degree is the most respected credential a person can hold in this industry. If you have the time and money, and are serious about a career in the gem industry, the GG course of study offered by the GIA should be your first choice.

The IGS certification program was created for everyone else. The founder of IGS and original author of the program, Donald Clark, has strong connections with the lapidary community. For years, he listened to amateurs giving inaccurate advice to others. For example, he heard things like: “If your blue stone has an RI of 1.625, then it is topaz, not aquamarine.” Those two properties, color and RI, also belong to tourmaline and a few rare minerals. Blue topaz and blue tourmaline have vastly different values. Not knowing the difference can be costly, in terms of both money and reputation.

Donald Clark believed that the problem stemmed not from the well-meaning lapidary sharing his incomplete knowledge, but rather that there wasn’t anywhere to learn gem identification, short of taking (what was back then) a $3,000 course. For them, he created IGS. It is dedicated to all the gem cutters, collectors, jewelers, and others wanting to know more about gems. The Professional Gemologist program was also created for those lacking the resources for a GG degree. A typical example would be a person making a midlife career change. This often involves working two jobs for a period, or the time consuming process of starting a new business.

What the certification tells a customer, or potential employer, is that the holder has proven their knowledge of gemology: that they are well versed in its terminology, the properties of gems, how they are valued, and that they possess the skills and knowledge to distinguish one gem from another. But let us be clear: having the IGS certification may open doors to a career in gemology. But it is the way an individual presents themselves and his or her actual experience and work ethic that determines success.

Do you accept students world-wide?

Please note that due to shipping restrictions, unfortunately we cannot accept students in the following countries: Belarus, The Democratic Republic Of The Congo, Côte d’Ivoire, Cuba, Democratic People’s Republic Of Korea (North Korea), Iran, Islamic Republic Of Iraq, Kazakhstan, Laos People’s Democratic Republic, Lebanon, Liberia, Myanmar, Palestinian Territory, Russia, Sierra Leone, South Sudan, Sudan, Syria, Western Sahara, Zimbabwe. However, students in those countries may take any of our Mini Courses because they don’t involve shipping a gem kit.

Start this Course Today

Become well-versed in the terminology of gemstones, the properties of gems, how they are valued, and how to distinguish one gem from another.

Professional Membership

Gain access to all that IGS has to offer plus the ability to take our 2 certification courses for a fee of $400 each.

More about membership

30-day money back guarantee


We believe that joining IGS will save you time, money and heartache on your gemstone education and purchases. Our community of fellow enthusiasts and professionals wholeheartedly agree, which is why we are able to confidently extend a full 30-day money back guarantee on your membership. We’ll also refund your purchase of the Professional Gemologist course or Diamond Specialist course within 7 days of purchase. Mini-courses are non-refundable.