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Gemstone encyclopedia

Every gemstone, explained

What each stone is, how it wears in jewellery, and what to ask before you choose one. Browse by colour, or go straight to a letter.

This encyclopedia is educational. Inclusion does not confirm current Ralph Jacobs stock, sourcing, availability or suitability for a particular jewellery design.

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Quick overview

Garnet

Garnet is a family of minerals, not one red stone. It occurs in reds, oranges, greens, purples and even colour-change blues, with a hardness of 6.5 to 7.5 depending on type.

Classification
Mineral group
Mohs hardness
6.5–7.5 (scratch resistance — one part of durability)
Wear considerations
Garnet ranges from 6.5 to 7.5 on the Mohs scale, depending on type, and has fair to good toughness. With proper care it is durable enough for any jewellery style, but it should not take hard knocks or rough wear. Demantoid is a little softer than other garnets.
Treatment
Typically untreated
Care
Warm, soapy water is a safe way to clean any garnet. Ultrasonic cleaners are usually safe for garnet, but not for stones with fractures. Steam cleaning is not recommended. A fracture-filled garnet…
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Individual gemstones vary. Care depends on treatment, setting and condition. Encyclopedia inclusion does not confirm availability.

Individual gemstones vary · care depends on treatment, setting and condition · birthstone traditions vary · encyclopedia inclusion does not confirm availability.