Sapphire — every colour except red

Sapphire is corundum in every colour except red (that is ruby). Blue is
the classic — iron and titanium colouring — but the fancy palette (pink,
yellow, green, padparadscha orange-pink) is where value hunting lives.

Value factors — blue saturation and evenness first; clarity second
(silk inclusions can be character or flaw depending on structure); cut
third — sapphire is usually cut for colour retention, not maximum sparkle.

Treatments — heat is standard and stable; diffusion and glass-filling
exist at lower grades, and disclosure separates good sellers from bad.

Wear — hardness 9 makes sapphire the great everyday fine gem: rings,
bracelets, heirloom duty.

The trade's identification skills — heat vs unheated, synthetic flame-
fusion vs natural — are taught hands-on in the identification course.

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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

“I love all subjects, especially metalsmithing. I just love to fire and shape things.”

— Angie K. (Singapore) · published student feedback

“I am using the skills in my everyday life and my spare time has become very productive.”

— Shirley M. (Philippines) · 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

Jewellery 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 expectWatch the gem webinars — the free replay libraryThe free gem webinar replay library explained — what the recorded sessions cover, how to wJade explained — jadeite vs nephrite, the distinction that mattersJadeite versus nephrite — the two jades compared in toughness, colour and value, with the

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