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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 · March · As listed by GIA

Aquamarine

Aquamarine is the green-blue to blue variety of the mineral beryl. This entry explains its colour, clarity, heat treatment, hardness and care, so you can judge it for everyday jewellery.

Classification
Mineral variety
Mohs hardness
7.5–8 (scratch resistance — one part of durability)
Wear considerations
At 7.5 to 8 on the Mohs scale, aquamarine is durable for jewellery as long as it is protected against scratching and hard knocks [cite ref="s3"]. Intense heat may make gems slightly more brittle, so the pointed corners and edges of heated stones need care [cite ref="s5"].
Treatment
Heat treatment to remove the greenish part of the colour and give a purer blue (common). Disclosed here under this guide's editorial standard of naming every known treatment; legal disclosure rules differ between countries., Fracture filling with resin or glass (less common). Disclosed here under this guide's editorial standard of naming every known treatment; legal disclosure rules differ between countries.
Care
Clean aquamarine with warm water, a little mild dish soap and a toothbrush, scrubbing gently behind the stone. Warm soapy water is always a safe choice. Ultrasonic and steam cleaners are usually…
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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.