Aquamarine

Step out of our shop in Swakopmund and walk to the end of the street: the Atlantic is right there, grey-blue under the morning fog, clear and pale in the afternoon sun. Aquamarine carries that same colour. Its name means "sea water", and it is hard to find a better word for it.

Namibian aquamarine comes from the Erongo region, the granite mountains about 150 kilometres inland. So a Namibian aquamarine bought on this coast brings the desert and the sea together in one stone.

What it is

Aquamarine belongs to the beryl family, the same mineral as emerald. Emerald takes its green from traces of chromium; aquamarine's softer blue comes from a different trace element. Beryl grows as long, six-sided crystals, sometimes large enough to hold in your hand, and aquamarine crystals are often remarkably clear.

Where it forms

Like tourmaline, aquamarine grows in pegmatites: pockets in granite where rare elements gather as the rock slowly cools. In the Erongo Mountains, some aquamarine crystals carry fine needles of black tourmaline inside them. Collectors prize those specimens; jewellers cut the clearest blue sections into gems.

Beliefs and legends

For a gem the colour of the sea, the legends are about water. Sailors believed aquamarine calmed the waves and kept them safe at sea, and in their stories it was the treasure of mermaids.

Other beliefs went further. Beryl, the family aquamarine belongs to, was said to protect its wearer in battle and in lawsuits, to make them unconquerable yet amiable, and to quicken the mind. Aquamarine was also thought to bring happiness in marriage, and it is still the gift for a 19th wedding anniversary.

Treatments, honestly

Many aquamarines come out of the ground slightly greenish, and most are gently heated to give a purer blue. The change is permanent and widely accepted. Some people prefer the natural sea-green tones, and we are happy to show you both.

How to judge an aquamarine

• Colour first. The deeper and purer the blue, the more valuable the stone. Pale aquamarines are lovely and much more affordable.
• Expect it to be clean. Good aquamarine is almost always free of visible inclusions. If you can see one easily, the price should reflect it.
• Size helps. Aquamarine's colour is gentle, so larger stones show it best. A well-cut stone of several carats is where the colour really comes alive.
• Look for life. A good cut makes the stone sparkle across its whole face, with no dull or watery centre.

Caring for your aquamarine

Aquamarine is hard and tough enough for everyday wear (7.5 to 8 on the Mohs scale). Clean it in warm water with mild soap and a soft brush, especially behind the stone where dirt collects. A stone with no visible inclusions can usually go in an ultrasonic cleaner, but warm soapy water is always the safest choice.

At a glance

Mineral	Beryl
Hardness	7.5 – 8 Mohs
Colours	Pale sea-blue to deep blue; some greenish
From	The Erongo region, Namibia
Treatments	Most are heated to a purer blue (stable). Disclosed per stone
Care	Warm soapy water, soft brush