• Pearls: Natural, Cultured or Imitation?
  • Learn from the Master
  • How will you choose your next gem purchase?
  • How do they make these things?

Gem and Jewellery Trade Secrets

       Discover your jewellery!

Start your journey at the source of gemmology: learn about gemstone origins, how gems are mined and who the middle-persons involved are that craft and carry these extraordinarily valuable minerals to market. Learn about gemology quality and value factors for all types of gems, from Diamonds to Coloured Stones, Organics to Jade. This comprehensive course gives you the knowledge and power to take control of your gem purchases (if you are a collector or enthusiast) or your sales process (if you are a designer or jewellery professional). Beyond the common trade practices and pricing, you will learn about imitations, synthetics and treatments sometimes used to enhance or even to deceive. Gemmology is a great chance for personal development.

You will never look at gemstones in the same way again!

You will Learn...

GM101 Coloured Gems - The Earth's Natural Wonders

Learn about a variety of beautiful natural minerals and how gemologists analyze and classify them. The flow from mine-to-market is understood together with common gem cutting practices.

GM102 Factors Affecting the Value of Gems

Unlike diamonds, the 4 C's are weighted differently when applied to coloured gems. Learn methods for evaluating colour in gems and how different clarity types are assessed. See a wide range of cutting styles in todays market and methods for carat weight assessment.

GM103 Synthetic, Imitation & Treated Gems

Imitation gems and treatments can be traced through history but synthetic or 'cultured' gems use more modern processes that are sometimes misrepresented at the buyer's expense. Understand the synthetics readily available in the market, imitations and treatments of gems and their proper disclosure practices in the gem trade.

GM104 Phenomenal Gemstones

An array of special gem materials which react in amazing ways to certain light sources are covered. From common to rare, students discover all about gem phenomena and phenomenal imitations.

GM105 Diamonds, the 4 C's and Beyond

Colour, Clarity, Cut and Carat are explained from a gemmological point of view. The origins and history of diamonds are reviewed and an understanding of the modern diamond trade is imparted.

GM106 Natural Diamonds, Simulants & Synthetics

Many materials are made to resemble diamonds; some can be easily identified, while others nearly identical. The differences between natural and synthetic diamonds are covered. Tips and quick practical tests are shared to assist in identification.

GM107 Pearls: Natural, Cultured & Imitation

Differences between the varieties of pearls readily available in the market today are identified. Origins of some of the most beautiful specimens as well as common imitations and tests are covered. South sea, Japanese and Chinese pearls are closely inspected.

GM108 Assessing Pearl Value

Varied examples are used to identify the different quality factors of pearls and how they affect price. Colour, lustre, shape, spotting, nacre thickness & make are amongst factors explained & observed.

GM109 Platinum, Gold and Silver

An overview of the history, terminology, science, testing and grading of metals is presented, as well as an analysis of the world's most impressive precious metal jewellery are discussed. Metal purity is documented through Trade- and Hall-marks which are inspected.

GM110 Jewellery Manufacturing

The history of jewellery manufacturing is as colourful as jewellery itself. This overview also focuses on today's manufacturing processes and factors that affect durability, quality and price.

GM111 Organic Gems

Materials produced by something living or once living are known as Organic Gems. Amber, Jet, Bone, Ivory, Shell and Coral are covered, with other less common but unusual types found in jewellery today.

GM112 Jade and Jade Imitations

As one of the most popular gems in the Far East, Jade has many imitations, and two genuine forms: Jadeite and Nephrite. Learn Jade's history, value factors, imitations & lore.

Over 1800 Gem Exhibits!

This popular course takes place in our 'Diamond Room' where participants are able to see, examine, scope and understand Tanja's collection of over 1,800 gems, jewellery pieces and examples, including rare and valuable specimens as well as common imitations found in jewellery markets in the region! Far from being a 'theory' course, this is an extremely hands-on programme guaranteed to raise your awareness of the jewellery you wear, buy, sell or design!

calendarBook Your Seat Now!

Join us for one of these fascinating sessions by simply giving us a call on 6221 5253 or email This email address is being protected from spambots. You need JavaScript enabled to view it. to go over your options!

You are browsing the old 2012-2018 JDMIS 'Experience' Curriculum!

In 2018, JDMIS underwent a comprehensive course evaluation process involving its education and industry partners. The results of this review was the new JDMIS 'Decennial' Curriculum that is most up-to-date and industry-relevant with established academic pathways to UK universities

Please click here to view the latest info and schedules of this course

This is a flagship course at JDMIS...
but there's much much more!

Comprehensive Jewellery Certification

JDMIS specialises in comprehensive industry-level training! We train jewellery professionals from around the region in a wide range of jewellery topics. We also help jewellery artists excel by incorporating into their work, the techniques and best practises used by the professionals! Check out our formal Diploma programmes and their modules, which are also offered as stand-alone skills certifications:  


Learn From The Best

The Jewellery Design and Management International School (JDMIS) is the only specialized school providing professional jewellery design, gemmology, fabrication and business training to the jewellery industry, artisan entrepreneurs and jewelelry enthsiasts.

We have uniquely structured courses ranging from intensive full-time diploma courses to compact 40 hour professional part-time certifications that focus on specific skills. Whether you are attracted by the idea of being a jewellery designer, need to upgrade your skills as a jewellery professional, or simply flex your creativity and express your own personal style, JDMIS can help you achieve and exceed your jewellery dreams!

Tanja Sadow, Dean and founder of the JDMIS is Singapore's most notable jewellery personality - having educated the trade and public for over 30 years with a unique international perspective that includes experience in all facets of the jewellery trade from Europe, the United States, South America and Asia.