Gemmology Diploma

Learn more about what you will study on Gem-A’s globally-recognised Gemmology Diploma course.

Further your knowledge of Gemmology

At Gem-A, we have supported thousands of students who want to advance their gemmological knowledge and secure a world-recognised and industry-respected qualification.
Our Gemmology Diploma is the most prestigious 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 learned 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.

Graduates of the Gemmology Diploma can apply for Fellowship of Gem-A, allowing them to use the letters FGA after their name. FGA Membership status conveys a student’s knowledge, integrity, membership of a professional body and commitment to professional development, and is highly valued within the gem industry.

Course Details

Duration

4 or 9 Months

Price

From £4,385

Qualification

Gem-A Level 6 Diploma in Gemmology

Study method

Gem-A London, online or at an Accredited Teaching Centre

Who can apply?

Only graduates of our Gemmology Foundation course can apply for the Gemmology Diploma

Eligibility criteria

To be eligible for the Gemmology Diploma, you must have first passed Gemmology Foundation

Course materials provided

Comprehensive Diploma course notes; practical handbook and workbook; Diploma stone set containing 20 rough and cut specimens. Those choosing to study online will also receive a travel microscope

If you have any questions regarding the courses, please contact education@gem-a.com

Read more detailed information about this course by downloading the syllabus above, or visit the Student Resources area where you can find our prospectus and other useful information.

GEMMOLOGY DIPLOMA

What will I learn?

Building on from the knowledge gained during the Gemmology Foundation, the Gemmology Diploma course covers a range of advanced skills and techniques.
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Gem treatments &
production

An in-depth look at treatments and synthetic materials, including their production, use, identification and the resulting implications for the gem trade, taking into account the ethical, environmental, and technological implications and applications of gemmology.
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Applying scientifc
principles

How to interpret results from advanced gem-testing equipment and apply scientific principles and concepts to solve gemmological problems, and to assess the validity, reliability and credibility of scientific information related to the study of gems.
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Gem testing &
information

How to select, organise and present relevant gemmological information using professional and technical vocabulary. Additionally, how to demonstrate a logical approach to gem testing, and the capability to acknowledge limitations and uses of certain tests.

I enjoyed every bit of it. I studied it for mainly pleasure and also in the hope I could in some way be involved in the industry… It was certainly challenging but I loved it

Dayanthi Ratnayake
Gemmology Foundation Alumni

How to Study with Gem-A

We have three different study options for you to choose from, in-person at our London HQ or through one of our Accredited Teaching Centres around the world, or by online distance learning (ODL). Find out more below.

Upcoming Gemmology Diploma courses

Use the table below to find an upcoming Gemmology Diploma course on-site at Gem-A London or online delivered by Gem-A.

Deadline for applications: 17 August 2025

Code Name Start Date DurationPrice (£)

Ready to apply?

Make sure to review the Terms and Conditions, for our courses, as you will need to agree to them when completing the application form.

COURSEWORK & EXAMS

How will I be assessed?

In order to help steer your learnings into an advanced understanding of gemmology, you will be assessed in the following ways.

Assessed Coursework

On the Gemmology Diploma, you will undertake four online assessments

Examinations

Two examination papers combining theory and practice, plus one practical exam

Practical Lab Class

The practical lab class is only applicable to Online Distance Learning students. 

TESTIMONIALS

Hear from our community

Frequently Asked Questions

As part of your student membership, you will have access to two online gemmology publications that are released quarterly: The Journal of Gemmology and Gems&Jewellery, as well as being eligible for a discount in the Gem-A Instruments shop. You will also have access to a special student ticket price for networking events such as the annual Gem-A conference. Students can also apply for a Totum Pro discount card (for UK discounts).

Unless there are proven mitigating circumstances, students will not be able to re-do any assessments. If you are in a situation that you believe would constitute mitigating circumstances, please contact your tutor as soon as you can. More information can be found in the Student Policies and Procedures.

Gem-A can consider additional support for individuals who are disabled, have a learning difficulty or long-term medical condition. If this applies to you, please contact our Student Support Officer at studentservices@gem-a.com to find out more.

Students will be using refractive index (RI) liquid in their practical gem testing sessions or lab classes when using a refractometer. RI liquid is commonly used in gemmology when using a refractometer. The Gem-A course extensively covers the appropriate use of refractometers, and therefore, to successfully complete the Gemmology Diploma, you will be required to use the RI fluid. In a classroom environment, the Gem-A tutors will provide you with appropriate information regarding the RI liquid, and you will be taught the recommended handling procedures. Only a tiny drop of RI liquid is used in testing, and the cap on the bottle is always replaced. It is your responsibility to ensure that you appropriately follow the instructions and information provided by your tutor on the use of the RI liquid. Gloves will be provided if you require them when using the RI liquid at the London teaching center.

RI liquid contains diiodomethane, and you may need to exercise precautions if you are pregnant, if you have certain medical conditions, and if you have sensitivity to, or are allergic to, this chemical. Again, your tutors will provide the required information on handling procedures. Please inform your tutors so that they are aware of your needs. If you are unsure, contact your doctor for advice. If you are pregnant, please consider that you may also be sensitive to the smell, which may make you nauseous.

If you are unsure about using RI liquid or if your doctor has advised against using it, please contact education@gem-a.com for further advice or for a copy of the Material Data Sheet.

For each course, the recommended self-study hours per week, including time for the reading of the course notes, completing any homework (onsite studies only), and end-of-block reviews and online assessments, are:

Gemmology Foundation

  • Evening: 6 to 8 hours
  • Daytime: 4 to 6 hours
  • ODL: 6 to 8 hours
  • ODL Fast track: 10 to 12 hours

Gemmology Diploma

  • Evening: 8 to 10 hours
  • Daytime: 6 to 8 hours
  • ODL: 10 to 12 hours

Diamond Diploma

  • Evening: 10 to 12 hours
  • Daytime: 8 to 10 hours
  • ODL: 8 to 10 hours

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