Amber and coral — the organic gems

Organic gems predate chemistry — and they need different care rules.

Amber — fossilised tree resin, tens of millions of years old. Warm to
the touch, floats in saturated salt water, glows under UV. The market's
imposters: copal (young resin, melts under a hot point) and pressed amber
(heat-fused small pieces — disclosed as "ambroid"). Colour enhancement via
heat is common and disclosed.

Coral — the reef skeleton: precious red/pink coral (now heavily
conservation-restricted) and bamboo coral substitutes. Dyed imitation is
rampant; provenance and disclosure decide legitimacy.

Care for both — soft (Mohs 2-4), heat-sensitive, chemical-hostile: no
ultrasonics, no perfume contact, wipe clean, store separately. They are
gentle-wear gems — pendants, earrings, brooches.

Ethics and identification of organics are part of the gemmology course's
trade-practice modules — and the subject of dedicated webinar sessions.

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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

“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

“An institute that provides an all rounded education in jewellery.”

— Geraldine C. (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

Birthstones by month — the video-era gift guideThe twelve birthstones with colours, hardness and gift notes — the fastest way to personalTanzanite — one hill in TanzaniaTanzanite explained — the blue-violet zoisite found on one hill, heat treatment, pleochroiGem treatments explained — heat, oil, filling and diffusionThe gem treatment landscape explained — heat, oiling, filling, irradiation and diffusion —The hardest gemstones — Mohs 8 and above for everyday wearThe hardest gemstones compared — diamond, corundum, topaz, chrysoberyl and spinel — with w

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