Garnet
Long considered to be protective stones that ward off negativity, garnets come in a range of stunning colours and their natural sparkle make them prized in the jewellery world.
Variety is the spice of life
Garnet is widely known as a deep red gemstone, however it comes in a whole spectrum of colours and varieties - pyrope (orange red, crimson, or dark red), almandine (red-purple), spessartite (autumnal reds, oranges and browns), demantoid (rich green), rhodolite (purple-red) and tsavorite (green).
History Bite
The word garnet is thought to come from the old English word ‘gernet’, meaning ‘dark red’, and the Latin word ‘granum’ meaning ‘grain’, because they were likened to deep red pomegranate seeds.
Garnets were favoured by stylish Victorians who wore the stones in jewellery, fashioned as roses.
Epic Proportions
Garnet crystals can be gemstone giants – in 1996, a single crystal weighing a whopping 37.5 tons was found near Alice Springs, Northern Territory of Australia. A tad too big for a ring, we think!
Geology lesson
Garnets are a group of silicate minerals. They’re extremely durable and have a high refractive index (sparkle). Gem quality garnets have either a vitreous (glass-like) or resinous (amber-like) lustre.
Garnets are durable, measuring 7 - 7.5 on the Mohs scale, so they’re ideal for cutting and polishing for jewellery. This also makes them fairly resistant to daily wear and tear.
Gem Specs
| Chemical Composition |
Composition Complex silicates with widely varying chemical composition but similar structures.
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| Colour |
Usually dark brownish or purplish red garnet and almost any colour expect blue.
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| Refractive Index |
1.74-1.94. Isometric.
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| Durability |
Hardness 6.5-7.5.
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| Crystal Structure |
Isometric (cubic)
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| Specific Gravity |
3.4-4.2
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Sources / Occurrence |
Czechoslovakia, India, North Carolina, Tanzania.
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Varieties
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Alamandite-usually dark brownish to purplish red Pyrope- dark to very dark purplish, pinkish, or blood-red
Spessartite- Orange to orangish-red.
Rhodolite- A mixture of pyrope and almandite with a distinctive purplish red colour.
Grossular- Various shades of orange, green, colourless, yellow, pink
Malaya-mixture of pyrope and spessartite. Colours vary from orange to peach, pink, or red.
Hessonite- An orange to brown variety of grossular garnet that has a distinctive swirled, "treacle" appearance under magnification.
Uvarovite- A fine green garnet, similar in appearance to tsavorite.
Tsavorite-An intense, emerald-like green grossular found only in Kenya and Tanzania
Andradite- Several varieties are known of this rare garnet, the best known of which is demantoid. Topazolite is an obsolete name once applied to yellow andradite.
Demantoid- Light to medium green with distinctive fibrous inclusions resembling horse-tails.
Imperial Garnet
Grape Garnet
Mandarin Garnet
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To ensure your jewellery remains as dazzling as the day you buy it, see our guide called Cleaning & Care - How to Keep Your Jewellery in Mint Condition.
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