Study Time

9 - 12 months


Gem-A Level 6 Diploma in Gemmology

Gemmology Diploma

Our Gemmology Diploma is the most prestigious international gemmological qualification in the gem and jewellery trade. You will look at a wider range of gems, synthetics and treatments, and will build upon the practical and theoretical knowledge learnt during your Gemmology Foundation course, leading to a more in-depth understanding of gemmology and the principles of gem testing and enhanced gem identification skills. Upon completion of the Diploma course you will be confident at handling, testing and identifying a wide variety of gemstones.

Graduates of the Gemmology Diploma course can apply for Fellowship of Gem-A, allowing them to use the letters FGA after their name. FGA status conveys a student’s knowledge, integrity, membership of a professional body and commitment to professional development, and is highly recognized within the trade. Your name will appear on the FGA and DGA register, available to the public to view on our website, so anyone can see that you are qualified and a registered Member with us — ensuring their peace of mind whilst advertising your knowledge and integrity.

Building on your knowledge learnt during the Gemmology Foundation, you will:

Have a broader knowledge of treatments and synthetic materials, including their production, use, identification and the resulting implications for the gem trade
Consider the ethical, environmental and technological implications and applications of gemmology
Interpret results accurately from advanced gem testing equipment
Be confident in applying scientific principles and concepts in solving problems relating to gemmology, and to assess the validity, reliability and credibility of scientific information related to gemmology
Learn to demonstrate a logical approach to gem testing, as well as be able to acknowledge limitations and uses of certain tests.
The origin and formation of gemstones and the various stages of the gemstone pipeline

The Diploma course materials build upon those received in the Foundation course. As part of the Diploma course material you will also receive:


Comprehensive Diploma course notes*

Gem set

Diploma stone set containing rough and cut specimens

Practical Workbook

Practical handbook and workbook

Crystal Models

Fluorite and rutile crystal models

Travel Microscope

All Diploma ODL students receive a travel microscope

* Chinese Traditional, Chinese Simplified, Japanese and French course notes are also available to purchase. Contact the Education department ( for prices.

> Assessed coursework (Four online assessments plus a written project) worth 20% of final grade
> Written examination (Diploma theory paper 1) worth 40% of final grade
> Written examination (Diploma theory paper 2) worth 40% of final grade
> Practical endorsement (tutorial) — completion essential — followed by written (practical) examination (Diploma practical paper 3) worth 100% of final grade

Successful completion of Gem-A’s Gemmology Foundation course. On-site and ODL language requirements: English qualification, e.g. IELTS (Level 7) or TOEFL (score of 95-120).

All ODL Gemmology Diploma students need to attend a Gemmology Diploma lab class and complete the Diploma Practical Certificate, to ensure that your practical skills develop to the same standard as those who attend on-site classes. The lab class will consist of practical tuition over several days, with a practical examination on the final day of the class. Students can attend a lab class as part of the course in the UK, USA or Japan (which will include exam), or may arrange practical sessions independently with a GAPP centre (these practical sessions will not include the exam; this will need to be arranged and sat separately during the January or June exam sessions).

The Diploma lab class gives ODL students the opportunity to familiarize themselves with a wide range of gem materials and gem testing techniques that will enable them to accurately test and identify gem materials.

Observation; the use of the 10× lens and the microscope
Effective and accurate use of the refractometer and how to interpret the results for a range of different materials
Use of specialist gemmological instruments including the spectroscope, polariscope, conoscope, dichroscope, colour filters and UV light to help determine the identity of gem materials as well as hydrostatic determination of specific gravity.
To handle and identify organic, non-organic, ornamental, rough, fashioned, mounted, natural, artificial and treated stones.
To demonstrate a logical approach to gem testing by selecting appropriate techniques for the material under test
To demonstrate safe and skillful practical techniques
To make, record and communicate reliable and valid observations and measurements with appropriate precision and accuracy
To interpret, explain and evaluate results clearly and logically using gemmological knowledge and understanding.

I studied the on-site evening course over one year, which I thoroughly enjoyed. I found learning with a small group of enthusiastic students and like-minded tutors enabled me to succeed. Studying the Diploma has helped me in my career, as having recently joined the gem trade I am now able to use my knowledge and skills with the confidence and assurance that I am making the right decisions.

Noah Thompson (London, England), Gemmology Diploma on-site student

Diamond Diploma, leading to eligibility for DGA status
BSc in Gemmology & Jewellery Studies (requires successful completion of Gemmology Foundation, Gemmology Diploma and Diamond Diploma)
Coloured Stones Grading Course

You can enquire about one of our courses by using the form below. Simply select the course you'd like to attend, fill in your details and click submit. A member of our Education Department will review your form before contacting you about your enquiry.

Alternatively, you can download a course application form from our Student Resources section. Once you've completed this you can email this to us at or post it to: Education Department, 21 Ely Place, London, EC1N 6TD.

If you have any other questions you can e-mail us at or call us on +(44) 0207 404 3334.


Gemmology Diploma



CodeCourse TitleCourse DaysStart DateFinish datePrice*
D18OMAR-PGemmology Diploma ODL (with UK lab class)Online CourseMar 19, 2018Jan 31, 20194465.00 GBP
D18OMAR-UGemmology Diploma ODL (with USA lab class)Online CourseMar 19, 2018Jan 31, 20194565.00 GBP
D18OMARGemmology Diploma ODL (without lab class)Online CourseMar 19, 2018Jan 31, 20193615.00 GBP
D18DSEPGemmology Diploma On-Site Daytime 4-month course (10:00 - 16:30)  NewTuesday, Wednesday (Thursday self study)Sep 11, 2018Jan 31, 2019TBC
D18ESEPGemmology Diploma On-Site Evening 9-month course (18:30 - 20:30)  NewWednesday and ThursdaySep 12, 2018Jan 31, 2019TBC
D18OSEP-PGemmology Diploma ODL (with UK lab class)  NewOnline CourseSep 17, 2018Jun 28, 2019TBC
D18OSEP-UGemmology Diploma ODL (with USA lab class)  NewOnline CourseSep 17, 2018Jun 28, 2019TBC
D18OSEPGemmology Diploma ODL (without lab class)  NewOnline CourseSep 17, 2018Jun 28, 2019TBC


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