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.
27 of 27 gemstone entries
Explore birthstones. Some months have several recognised stones and birthstone traditions vary. Association does not determine suitability, value or availability.
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Quick overview · March birthstone
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…
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.