Gemmology is a science that is concerned with gemstones and other materials used for personal adornment or objet d’art. It is a scientific discipline that has evolved from mineralogy — a branch of geology.

Twenty-first century gemmology involves the scientific study of gemstones (diamond, ruby, sapphire, emerald etc), ornamental materials (lapis lazuli, malachite), biological gem materials (amber, coral, ivory), and their synthetic counterparts as well as imitations. These materials must be identified and discriminated using a combination of established scientific fact, specialised gem testing instruments, and a comprehensive range of gem testing techniques. With advances in technology the academic and practical challenges being offered to the working gemmologist are ever increasing.

Although many people may not have heard of gemmology, it is not a new science. Long before The Gemmological Association of Australia was formed (in 1945) the world’s scientists were fascinated by the special properties possessed by gemstones.

For millennia, civilised man has been captivated by the beauty, mystery, rarity and value of what soon became known as (precious) gemstones. These much sought after objects of beauty and desire included diamond, ruby, sapphire, emerald, and pearl. While the adjectives precious and semi-precious are no longer used by gemmologists, today over 150 special minerals that posses the desirable attributes of beauty, rarity, and durability are termed gemstones. It is the scientific study of these very special minerals that forms the basis of the science of gemmology.

Over recent years ever-inventive man has duplicated many of Nature’s masterpieces, and in the process created precise man-made duplicates (synthetics) and very effective look-alikes (imitations). In addition, numerous techniques have been discovered for artificially enhancing the beauty of lower quality gemstones. The identification of these offers a continuing challenge to gemmology and gemmologists.

Gemmology is a science that is expanding at an exponential rate. If you wish to undertake the challenge of learning and understanding the science of gemmology, then The Gemmological Association of Australia’s courses in gemmology are for you.


By modern definition, a gemstone is a mineral or other natural material that is beautiful enough, durable enough, and rare enough, to be used for personal adornment or for the embellishment of personal possessions.

Most gemstones are rather rare minerals. They are naturally occurring inorganic crystalline elements or compounds that have chemical compositions and physical properties that are fixed or may vary between very fixed limits. Gemstones display the desirable attributes of beauty, rarity, and durability.

Other materials, that are less commonly used for gem purposes include:

  • rocks, that are formed from mixtures of minerals e.g. lapis lazuli.
  • non crystalline materials e.g. amorphous opal.
  • ornamental materials (ornamentals) that are those minerals which due to their lack of transparency owe their beauty to their body colour and/or attractive pattern of colours e.g. malachite.
  • Biological (organic) gem materials, which are materials produced by living organisms e.g. ivory, amber, or precious coral.

With respect to gemstones:

  1. Most are single minerals, and not other materials.
  2. Of the more than 3,000 known minerals found in the earth, the gem minerals total about 150.
  3. Gem minerals are very minor constituents of the ‘living planet’ known as planet Earth.

Today many gemstones are being value-enhanced by the application of various treatments to the gemstone or gemstone rough. Although the original materials may have a natural origin, man’s intervention has converted these materials into value-enhanced gemstones e.g. heat treated ruby and sapphire, ‘oiled’ emerald, irradiated coloured diamond, diffusion-treated sapphire.

In contrast, synthetics and imitations can not be described as gemstones; for essentially they are man-made. Therefore:

  • A synthetic or artificial gemstone is a man-made material having a chemical composition, crystal structure, and physical properties that are almost identical to those of a (natural) gemstone. E.g. synthetic sapphire, synthetic diamond.
  • Imitations are man-made (manufactured) products that only visually resemble the gemstone they are intended to simulate. E.g. glass, plastic, composite stones which are made from several components.


The key-word is knowledge … that is knowing.

At some stage in their life, almost every person buys or obtains a gemstone or at least one piece of gemstone-set jewellery. If you are aware of the differences between gemstones, value-enhanced gemstones, synthetics and imitations, then you know what you have and you will not be duped by value-enhanced gemstones, synthetics or imitations. If you are purchasing you can choose which you want.

There are many coloured stones which provide less expensive alternatives to the more expensive traditional gemstones of diamond, ruby, sapphire, and emerald. Do you know what coloured stones are available and what are their important characteristics? How often are these synthesised, imitated, or value-enhanced?

It you are a fossicker, or a lapidary, will you know whether you have found a piece of genuine rough gem stone, or perhaps a fragment of water-worn glass? If you facet gemstones, as a hobby or for profit, how and where will you learn how to correctly orient rough to achieve the best display of colour through the table of the gemstone you are about to facet?

For those who travel overseas, the opportunity to purchase gemstones cheaply in Asian countries must to be tempered by the knowledge of obvious pitfalls. That ‘bargain purchase’ often can let you down badly, if you return home only to discover that poor cutting has seriously undermined the value of your bargain gemstone, or even worse, you bought a synthetic or an imitation. Determining whether your bargain gemstone been value-enhanced is yet another challenge the tourist must overcome.

Factually, the more gemmological knowledge you can acquire, the more potential exists for its use.

Gemmologists come from every walk of life. The Gemmological Association of Australian has gemmologist members who are gem merchants, jewellers, geologists, antique dealers, doctors, dentists, pharmacists, librarians, shop assistants, secretaries, home makers … the list is endless.

Remember, the appeal of gemmology is universal.


Gemmologists identify gemstones, ornamental materials, biological gem materials, and their synthetics (exact duplicates), imitations (look-alikes), and value-enhanced forms, and, as well, evaluate their quality. The gemmologist appreciates the desirable attributes that make gemstones — their beauty, rarity, and durability.

In their day-to-day work gemmologists may do any or all of the following tasks:

  • Identify near-colourless gemstones such as diamond, coloured stones, ornamental materials, rocks, and biological gem materials using a combination of visual observation, examination under magnification using the gemmologist’s 10x hand and the gemmologist’s binocular microscope, and a range of specialised gem testing instruments.
  • Discriminate natural gemstone’s from their man-made synthetics and imitations.
  • Identify and discriminate all value-enhanced and otherwise artificially treated gemstones, ornamental and biological gem materials.
  • Assess the quality of all gemstones and other gem materials.
  • Assess and quantify damage to gemstones and gem materials.
  • Assess a stone’s durability and suitability to a particular purpose.

Gemmology, the science of gemstones, requires that the gemmologist identify gemstones using his or her specialised knowledge and appropriate gem testing instruments.

Gemmologists usually work indoors, either independently or as employees of gem merchants, manufacturing jewellers, wholesale jewellers, or retail jewellers. At times gemmologists may be required to work under quite primitive conditions to identify and evaluate parcels of rough and cut gemstones that are offered for sale in often quite remote mining localities. It is indeed a fact that geologists and mining engineers who are also gemmologists are much in demand.

Gemmologists must have a basic love for gemstones, an inquiring mind, a reasonable academic ability, common sense, dedication, patience, a good memory, and a meticulous attention to detail.



  • Fluent English language skills and the ability to understand technical scientific terminology.
  • Legible hand writing in English, especially for examinations.
  • Basic computer skills including proficiency in MS Word as well as access to email and internet.
  • Sufficient dexterity and eyesight for handling small stones and tools.
  • In addition to time required for classes, we recommend a minimum of eight additional hours per week of independent study for the face to face mode (considerably more for intensive students).


There are three modes of study:

  1. In-house – provided at the teaching centres in Sydney, Brisbane, Melbourne, Perth and Adelaide. As well as evening classes, students in Queensland may choose to attend block classes instead, comprising 5 or 6 four-day blocks on selected dates distributed between February to September.
  1. Flexible – students complete theory components via distance learning (course materials supplied) and complete their practical (prac) in two one-week blocks: one in June, and one in September. In first year these blocks are five days long and in second year they are seven days long.

WA flexi students complete the theory component by distance learning (course materials supplied) and the prac by:

  1. first year 4 x three-day blocks, and
  2. in second year 5 x three-day weekends spread throughout the year.
  1. Intensive – offered in NSW and Victoria as a one-year intensive course. The content and other features of the course are the same as the two-year course and it allows participants to complete the work in one year.


Strictly controlled examinations are held annually in each teaching centre in October/early November. You are required to attend a minimum of 75% of classes and will be assessed on coursework, with the bulk of assessment based on theory and practical examinations. A minimum standard is required in first year before moving on to second year.

Students are also required to submit theory-based assignments throughout the year and in Gemmology 2 they must identify a prescribed minimum number of gemstones in the practical sessions.

Flexi students will be required to attend two practical block sessions at mid-year and end of year prior to undertaking exams.


The course attracts anyone with an interest in gemstones who wants to study them in depth. This ranges from enthusiasts who undertake the course for their own satisfaction, to people involved in the jewellery and mining industries and allied trades who wish to deepen their knowledge and enhance their career development

Some of the people who have studied with us include:

  • Jewellery manufacturers, designers, retailers and wholesalers.
  • Dealers in estate or antique jewellery.
  • Gem and/or diamond commercial trade or collecting.
  • Lapidaries.
  • Mining laboratory specialists.
  • People from all walks of life who have a passion and enthusiasm for gemstones.

Upon successful completion of this course graduates are entitled to apply for GAA Fellowship (through their local State Division) enabling the use of the internationally recognised post-nominal FGAA. They also receive:

  • the GAA Diploma in Gemmology Certificate; and
  • benefits of GAA membership and Fellowship.


Students are provided with:

  • electronic course notes
  • student online learning tools
  • Practical Gemmology Handbook
  • GAA’s Values of the Refractive Index and Specific Gravity of Commercially Known Gemstones

Wider reading is also encouraged, some of the texts that we recommend are:

  • The Australian Gemmologist, Journal of GAA
  • Journal of Gemmology, Journal of Gem-A
  • Gems & Gemmology, Journal of the GIA
  • Anderson, B. W. & Jobbins, E. A., 1990. Gem Testing. 10th ed. London: Butterworth & Co.
  • Campbell-Pedersen, M., 2010. Gem and ornamental material of organic origin. London: NAG Press.
  • Dominy, G. M., 2015. Handbook of Gemmology. 3rd ed., on DVD, with digital formats for Windows, Apple and Android devices.
  • Gemological Institute of America, 1995. GIA Gem Reference Guide. USA: GIA.
  • Liddicoat, R. T. Jnr., 1989. Handbook of Gem Identification. 12th ed. GIA.
  • O’Donoghue, M., ed., 2006. Gems. 6th ed. Oxford: Butterworth-Heinemann.
  • Read, P. G., 2005. Gemmology. 3rd ed., Sydney: Elsevier Butterworth Heinemann.
  • Schumann, W., 2013. Gemstones of the World. 5th ed. New York: Sterling.

Students are required to purchase certain gemstone handling tools that are available via the GAA shop  (the list of required equipment and order form is provided in the enrolment form).



You must be adept at handling gemstones and be able to confidently use a pair of diamond gem tweezers and a loupe. If you have no experience, you should enrol in our gemstone handling course (at extra charge).

The course is entirely practical and does not require formal study. However, students are required to read sections of the supplied Diamond Grading Manual to familiarise themselves with the theoretical aspects of the practical work that will be carried out in the next class.


At the completion of the Practical Diamond Grading course, students will sit a 3 hour practical examination with a number of components to assess skills obtained throughout the course.


Upon successful completion of this course, which includes a practical exam and assignment, graduates receive the GAA Practical Diamond Grading certificate.

Techniques of gemstone identification are a necessary skill to have as a valuer. The diamond courses do not specifically teach how to value gems or jewellery. For more information on becoming a Registered Valuer, please contact the National Council of Jewellery Valuers at www.ncjv.com.au



The prerequisite is successful completion of Practical Diamond Grading.

Please note that Practical Diamond Grading and Advanced Practical Diamond Grading are required elements for the completion of the Diploma in Diamond Technology.

The course is self-paced and entirely practical and does not require formal study, however, set notes should be read prior to each class.

Students are supplied with a comprehensive manual which covers all the practical aspects covered in the classes and can be used as a future reference.


Continuing assessment by the facilitator as tasks are completed.


Upon successful completion of this course, graduates receive the GAA Advanced Practical Diamond Grading certificate.

Techniques of gemstone identification are a necessary skill to have as a valuer. The diamond courses do not specifically teach how to value gems or jewellery. For more information on becoming a Registered Valuer, please contact the National Council of Jewellery Valuers at www.ncjv.com.au



Diploma in Gemmology is recommended but not a prerequisite for Diamond Technology Theory.

Minimum of 3 hours private study time per week for approximately 25 weeks (varies according to state).

Fluent English language skills and the ability to understand technical scientific terminology, legible hand writing in English, especially for examinations and basic computer skills including proficiency in MS Word as well as access to email and internet are all required.


Strictly controlled examinations are held annually in each teaching centre in October/early November. You are required to attend a minimum of 85% of classes and will be assessed on coursework, with the bulk of assessment based on theory examinations.

Students are also required to submit and present a diamond research paper.


Upon successful completion of this course (Diamond Technology Theory), the Practical Diamond Grading course and the Advanced Practical Diamond Grading course, graduates receive the Diploma in Diamond Technology. Graduates of the Diploma in Diamond Technology are also entitled to apply for the post-nominal DipDT (through their local State Division).

Our graduates work in diamond grading, retail and wholesale, mining, trading, design and manufacture, education, lapidary and faceting, in laboratories and valuations, research and science, prospecting and fossicking and, of course, auctions. Our courses will enhance your knowledge of diamonds and add depth to your passion.