Tanzanite — one hill in Tanzania

Tanzanite is blue-violet zoisite from a single hill block in Tanzania —
discovered 1967, source still essentially one place. Geology's lottery
ticket.

The look — pleochroic: one crystal shows blue, violet AND red-brown
from different angles; cutters orient for the blue-violet face. Heat
treatment converts brownish natural material to the blue market wants —
standard and stable.

Buying notes — deeper saturated stones command premiums; large clean
stones are rare (the hill is finite). Hardness 6-7: earrings and pendants
over everyday rings.

The trade lesson — single-source gems trade on scarcity stories; the
gemmology course covers how to value them sanely.

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Go deeper — free

Watch the free replays at the gem webinar library — the gem e-book is the written companion. When curiosity becomes commitment, the gemmology foundation course is the ladder's first rung (online entry: GT100e); dates on the calendar. Play Name That Gem to train the eye between sessions.

What students say

“Attended the courses here and it's worth way more than what you have to pay for. The instructors are all super approachable and welcoming everytime they see you. The tools needed are provided and you get to bring home the crafts that you make during the class. Even the class schedules are pretty flexible. I enjoyed myself here a lot and will definitely sign up for more classes.”

— Nebulla L. (Singapore) · published student feedback

“There is a very wide range of jewellery design programmes. Tanja's an expert and she encourages the class and is also open for catch-ups later.”

— Cecilia O. (Singapore) · published student feedback

Free ways to explore

No sign-up, no payment — start with any of these.

WWatch a free gem webinarFREE
Full recorded sessions — the best free starting point.JJDMIS on YouTubeFREE
Course previews, blended-learning explainers and school life.FFree jewellery webinar replaysFREE
Recorded sessions on design and the jewellery industry.DDownload the gem e-bookFREE
The school's free guide to gems — pairs with the replays.

Keep exploring

Watch the gem webinars — the free replay libraryThe free gem webinar replay library explained — what the recorded sessions cover, how to wJewellery Video — watch, learn and make with JDMIS video educationVideo-first jewellery education — recorded gemmology webinars, online course options and bEmerald — the garden gemEmerald explained — the beryl family's green treasure, why gardens (inclusions) are expectDiamond shapes explained — the 10 cuts and what they suitThe ten classic diamond shapes compared — round brilliant, princess, oval, emerald cut and

See the online and blended options

Gemmology can be started fully online, and every classroom course at JDMIS has a video-supported path.

Visit jdmis.edu.sg