Red From the Island of Gems
Ruby is the red variety of corundum — the same mineral family as sapphire — coloured by chromium. (Every other colour of gem corundum is called sapphire; only red is ruby.) With a hardness of 9, ruby is one of the most durable gems for jewellery.
Sri Lankan rubies tend toward lighter, brighter pinkish-reds rather than the deep "pigeon's blood" red associated with Myanmar. These lively Ceylon rubies are valued for their brilliance and transparency.
What Affects Value
- Colour — a pure, vivid red is most prized; the finest is "pigeon's blood." Too pink and a stone may be classed as pink sapphire.
- Clarity — eye-clean rubies are rare and valuable; fine "silk" can soften the glow.
- Cut & carat — clean larger rubies are extremely rare and rise steeply in price.
- Treatment — heat treatment is common and accepted; disclosed always.
Ruby vs Pink Sapphire
Because both are chromium-coloured corundum, the boundary is about colour intensity — see our pink sapphire guide. Certification settles which is which.
Buying Tip
Buy from a licensed dealer and certify significant stones. Read our guide to buying Ceylon gems.
Visit the Source
Browse Ratnapura accommodation and the Island of Gems overview.
Quick Facts
| Mineral | Corundum (the red variety) |
| Cause of colour | Chromium |
| Hardness | 9 (Mohs) |
| Ceylon character | Lighter, brighter pinkish-reds |
| Main SL source | Ratnapura gem fields |
| Treatment | Heat treatment common (disclosed) |
Frequently Asked Questions
What's the difference between ruby and sapphire? They're the same mineral (corundum); only the red variety is called ruby — every other colour is sapphire.
How are Ceylon rubies different from Burmese? Sri Lankan rubies tend toward lighter, brighter pinkish-reds, prized for brilliance and transparency, rather than the deep "pigeon's blood" red.
When is a stone a ruby vs a pink sapphire? It comes down to colour intensity; certification settles borderline cases.
Is ruby durable? Very — at hardness 9 it's ideal for everyday jewellery.