Study Time

6 - 9 Months


Gem-A Level 5 Diploma in Gem Diamond

Diamond Diploma

Diamonds are the most commercially important gem material, with a huge global market. A good understanding of diamond and diamond grading is essential for the buying, selling and trading of diamond. One of the most comprehensive and valuable diamond qualifications worldwide; with our Diploma you will gain a comprehensive understanding of diamonds and how the diamond market operates. You will study all of the factors that affect a diamond’s appearance and properties, learn about diamond grading, the 4Cs (carat weight, colour, clarity and cut) and the other factors that influence value, as well as how to identify and recognize imitations, synthetics and treatments.

Graduates of the Diamond Diploma course can apply for Diamond Membership of Gem-A, allowing them to use the letters DGA after their name. DGA status conveys a student’s knowledge, integrity, membership of a professional body and commitment to professional development, and is highly recognised 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.

To recognize and describe the structure of a diamond and how this relates to its physical and optical properties
The different diamond types and colour mechanisms occurring within diamonds
To recognize and distinguish between natural, treated and synthetic diamonds and to compare and identify a diamond and its simulants
How to make, record, sketch and communicate reliable and valid observations of rough diamond crystals
The geological processes involved in diamond formation and how occurrence and locality affect the mining and recovery of diamonds
The cutting of a diamond, including the history of diamond cutting and style
To describe the diamond grading process, the various systems used and how grading affects the value of a diamond
The ethical, social, economic, environmental and technological implications of the diamond supply chain
To accurately interpret, explain, evaluate and communicate diamond testing results

Fully illustrated Diamond Diploma course notes

Gem set

Set of diamond simulants

Diamond Grading Manual

Gem-A's Diamond Grading Manual and workbook

Crystal Models

Diamond crystal models

Diamond Gem Kit

Portable diamond instrument kit, containing 10× lens, thermal tester, stone tweezers, stone cleaning cloth and a long-wave ultraviolet key-ring

> Assessed coursework (Four online assessments plus a written project) worth 20% of final grade
> Written examination (Diamond theory paper 1) worth 80% of final grade
> Practical examination (Diamond practical paper 2) worth 100% of final grade

On-site and ODL language requirements: English qualification, e.g. IELTS (Level 7) or TOEFL (score of 95-120).

All ODL Diamond Diploma students need to attend the five-day Diamond Grading and Identification Course, 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 in the UK or Japan which will include the exam.

The Diamond Grading and Identification Course allows ODL students the opportunity to familiarize themselves with diamonds and diamond testing techniques that will enable them to accurately test, identify and grade diamonds.

> To handle a range of rough, cut and polished diamonds, both loose and mounted/set in jewellery
> How to colour and clarity grade to internationally-recognized standards
> How to estimate the weight of a mounted diamond and understand the limitations of grading such diamonds
> Observation of synthetic diamonds, to identify a diamond and differentiate it from its simulants, including synthetic moissanite, glass and CZ, etc.
> To identify clarity enhancement treatments, such as laser drilling and fracture filling
> How to grade diamonds for cut, polish, symmetry and proportions in relation to international tolerances
> The correct lighting and observation techniques for consistent diamond grading

The course will also cover a review of the requirements for the practical aspects of the Diamond Diploma practical examination.

Having studied the Diamond Diploma, I am far more confident when buying diamonds to use in my designs. Being introduced to rough diamonds has definitely influenced my work. The course notes and instruments are excellent and the depth of knowledge of the tutors combined with their enthusiasm for the subject is inspiring. ODL allowed me the flexibility to study around my work whilst having the reassurance that my tutor was there to answer any questions and support me throughout the course.

Sally Spencer (Oxford, England), Diamond Diploma ODL

Gemmology Foundation, leading to Cert GA status and eligibility to take Gem-A's Gemmology Diploma
Gemmology Diploma, leading to eligibility for FGA 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.


Diamond Diploma



CodeCourse TitleCourse DaysStart DateFinish datePrice*
G18OMAR-PDiamond Diploma ODL (with UK lab class)Online CourseMar 12, 2018Jan 28, 20192980.00 GBP
G18DSEPDiamond Diploma On-Site Daytime 4-month course (10:00 - 16:30)  NewMondaySep 10, 2018Jan 28, 20193340.00 GBP
G18ESEPDiamond Diploma On-Site Evening (18:30 - 20:30)  NewWednesday and ThursdaySep 12, 2018Jan 31, 20193080.00 GBP
G18OSEP-PDiamond Diploma ODL (with UK lab class)  NewOnline CourseSep 24, 2018Jun 28, 20193140.00 GBP


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