Garnets – Colours, Origins, Types & Value Guide | GemMine
What Are Garnets?
Garnets are one of the most diverse and fascinating gemstone groups in existence, encompassing over 20 species and an extraordinary range of colours. While many people associate garnets with deep red stones, they actually occur in virtually every colour — from vivid green (Tsavorite and Demantoid), bright orange (Spessartine and Mandarin), and yellow (Mali) to rare blue colour-change varieties. Garnets are silicate minerals with a hardness ranging from 6.5 to 7.5 on the Mohs scale.
Types of Garnets
The garnet group includes many distinct species, each with unique properties:
- Pyrope – Classic deep blood-red garnets, often from Bohemia and Arizona. The most traditional garnet variety.
- Almandine – The most common variety, with a reddish-brown to deep red colour, found in India, Sri Lanka, and Brazil.
- Spessartine (Mandarin Garnet) – Brilliant orange to red-orange garnets from Namibia and Nigeria, highly prized for their vivid colour and brilliance.
- Grossular – Tsavorite – One of the most valuable garnets, a vivid emerald-green to yellowish-green variety found only in Kenya and Tanzania.
- Grossular – Hessonite – Orange-brown to cinnamon-coloured garnet, traditionally from Sri Lanka.
- Andradite – Demantoid – The most valuable garnet variety, a vivid green stone with extraordinary dispersion (fire) exceeding even diamond. Found mainly in Russia and Namibia.
- Andradite – Topazolite – Yellow to yellow-green variety from the Alps.
- Rhodolite – A rose-pink to purplish-red hybrid of pyrope and almandine, from Mozambique and Zimbabwe.
- Colour-Change Garnet – A rare variety appearing blue or teal in daylight and purplish-red under incandescent light, mainly from Madagascar and Tanzania.
- Mali Garnet – Yellow to green hybrid of andradite and grossular, found exclusively in Mali.
Where Do Garnets Come From?
Garnets are mined across the globe:
- Africa (Tanzania, Kenya, Mozambique, Namibia, Mali) – Key source for Tsavorite, Demantoid, Rhodolite, Spessartine, and colour-change varieties.
- Russia (Ural Mountains) – Historic source of the finest Demantoid garnets, often with distinctive horsetail inclusions.
- India, Sri Lanka & Brazil – Major sources of Almandine and Hessonite garnets.
- USA (Arizona) – Pyrope-Spessartine garnets known as "ant hill garnets" from the Navajo Nation.
Ethical Mining & Sustainability
Most garnet mining operations are small-scale and have a lower environmental footprint compared to diamond or ruby mining. Tsavorite from Scorpion Mine in Kenya operates with community benefit programmes. GemMine stocks garnets from responsible sources with preference for certified supply chains.
Garnet Rarity & Value
While common red garnets are affordable, the rarer varieties command significant prices:
- Demantoid Garnet – Top quality Russian Demantoid can exceed £3,000/ct for fine stones.
- Tsavorite Garnet – Fine quality stones over 3ct can reach £2,000-5,000/ct.
- Mandarin/Spessartine Garnet – Top Nigerian specimens reach £1,500-3,000/ct.
- Colour-Change Garnet – Rare Madagascan examples can exceed £2,000/ct.
Garnet Price Guide (GBP)
| Variety | Quality | Price per Carat (GBP) |
|---|---|---|
| Red Garnet (Almandine/Pyrope) | Commercial | £15–£80 |
| Rhodolite | Fine | £80–£350 |
| Mandarin/Spessartine | Fine | £400–£1,500 |
| Tsavorite | Fine | £600–£5,000 |
| Demantoid (Russian) | Fine | £1,000–£3,500+ |
| Colour-Change Garnet | Fine | £800–£2,500 |
Prices are indicative and vary by size, clarity, and certification.
Why Choose Garnets?
Garnets offer exceptional value compared to the "big three" (ruby, sapphire, emerald) while delivering vivid, vibrant colour. Rare varieties like Demantoid and Tsavorite are genuinely investment-worthy due to limited mine supply and growing collector interest. GemMine offers a curated selection of garnet varieties spanning every colour of the spectrum.