Diamond Grading & Identification Lab Class

This five-day in-person diamond grading course, culminating in a final exam, has been especially designed by Gem-A to serve both Diamond Diploma online distance learning (ODL) students and other professionals looking to expand their diamond skills and experience in a short period of time.

Start or extend your diamond studies

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.

Forming the practical component of the Diamond Diploma for ODL students, this practical lab class is also available as a stand-alone short course, allowing you the opportunity to familiarise yourself with diamonds and diamond testing techniques that will enable you to accurately test, identify and grade diamonds. This short course consists of practical tuition for 5 days days, with a practical examination on the 6th day of the class.

Our graduates go on to successful careers in a number of areas in the trade, such as buying, selling, auctioning or valuing diamonds and diamond-set jewellery. Diamond Diploma graduates must apply for Gem-A Membership in order to continue to use the post-nominal DGA after their name — a sign of excellence in the trade.

Course Details


6 days


from £1,350


Gem-A Diamond Practical Diamond Certificate

Study method

In-person or Gem-A London

Who can apply?

Anyone working in any sector of the trade who has an interest in grading diamonds.

Anyone looking to advance existing skills.

Current Gem-A Diamond Diploma ODL students are required to take this course as part of their exam.

Equipment provided*

Diamond grading manual

Diamond practical workbook

Portable diamond instrument kit, containing 10× loupe, thermal tester, stone tweezers, stone cleaning cloth, estimator gauge, long-wave UV key ring and a zip case.

*Only for short course applicants 

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

Diamond Grading & Identification Lab Class

Short Course Applicants

No prior diamond experience is required to take this course. Instead, we look for individuals who are passionate about diamonds and want to improve their practical skills. To apply, simply select your chosen dates via the Upcoming Lab Classes tab and enquire with our team via education@gem-a.com

ODL Diamond Diploma Students

All students studying the Gem A Diamond Diploma via the ODL route are required to attend a Diamond Diploma Lab Class to complete their course. The Diamond Grading & Identification Lab Class takes place over five days and on the sixth day you will be required to take a practical assessment.

What will I learn ?

Diamond Grading & Identification Lab Class - diamond diploma - VS1C©GemA HM 1

Dive into the World of Diamonds

Throughout the five days of the Lab Class you will handle rough, cut and polished diamonds, both loose and set in jewellery. You will learn how to colour and clarity grade diamonds to internationally recognised standards and will be taught how to estimate the weight of a mounted diamond and the limitations this may cause when grading.

Diamond Grading & Identification Lab Class - diamond diploma - Diamonds 0003 PD

Understanding Diamond Diversity

During the Lab Class you will observe natural, synthetic diamonds and simulant diamonds, including common materials like moissanite, glass and cubic zirconia. You will be guided through clarity enhancement treatments, like laser drilling and fracture filling, and will discover how to identify them.

Diamond Grading & Identification Lab Class - diamond diploma - Diamond ©GemA 0527

Advanced Diamond Grading Techniques

On the final days of the course, you will tackle grading diamonds for cut, polish, symmetry and proportions in relation to international tolerances, utilising the best lighting conditions and observation techniques at all times.

The course will cover

✔️ How to handle a range of rough and polished diamonds.

✔️ The correct lighting and observation techniques for consistent diamond grading.

✔️ How to grade diamonds for cut, including polish, symmetry and proportions in relation to international tolerances.

✔️ How to colour and clarity grade to internationally recognised standards.

✔️ Weight estimation of mounted diamonds with an understanding of the limitations of grading diamonds in jewellery.

✔️ Identification of a diamond and how to differentiate it from its simulants, including synthetic moissanite, glass and CZ, etc.

✔️ Detection and identification of clarity enhancement treatments, such as laser drilling and fracture filling.

✔️ Introduction to the observation of synthetic diamond.

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

Upcoming Diamond Grading courses

Use the table below to find an upcoming Diamond Grading & Identification Lab class on-site at Gem-A London.

Code Name Start Date DurationPrice (£) Enquire

Ready to apply?

If you wish to apply by post/email please download our PDF application form and send to our London HQ or email to education@gem-a.com. Make sure to review the Terms and Conditions, as you will need to agree to them when completing the application form.


How will I be Assessed?

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


The Diamond Grading & Identification Lab Class concludes with an examination paper. Those studying via the Short Course option will receive a Gem-A Diamond Practical Certificate upon successful completion of the exam.

Practical Lab Class

The Practical Lab Class is one of two in-person requirements for all ODL students. The second is a final examination that needs to be taken in-person at Gem-A HQ, at a GAPP Centre or via an ATC.


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What's next?

Once you’ve completed the Diamond Diploma you can progress through the following routes

Diamond Diploma

Diamond Diploma Awarded

Eligibility for DGA membership status

Diamond Grading*

Gain your Diamond Practical Certificate

BSc in Gemmology & Jewellery Studies

Gain your BSc degree awarded by Birmingham City University

*Optional: These courses or classes are not required to become a FGA and/or DGA member, or for applying for the BSC in Gemmology & Jewellery Studies delivered by Birmingham City University.