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Aquamarine Gemstone

What is Aquamarine?

This is one of the world’s most popular and well-known gemstones. Often found with great clarity in a light yet energetic blue.

Aquamarine is a real favourite of many gem collectors and in a world that’s becoming more and more polluted, Aquamarine offers us all a breath of fresh air.A member of the Beryl family, Aquamarine’s characteristic pale blue colour is created by the presence of iron. Likewise, all members of the Beryl family obtain their colours by the presence of metallic elements, without which pure Beryl remains colourless.

Gemstones that are coloured by nature in this way are known as allochromatic. Aquamarine’s younger sister Morganite is coloured by manganese, and its older and more complicated sister, Emerald, receives her personality from the presence of chromium, iron and vanadium.

Its name is derived from the Latin “aqua” for “water” and “mare” for “sea”, and many superstitions and legends regarding the sea have been attached to the gemstone over the years. Believed to be the treasure of mermaids, the gem is said to be especially strong when submerged in water.  When its powers seemed to dwindle, the gem would be placed in water on the night of a sparkling full moon.In times gone by, as a very last resort, sailors caught in a storm were believed to throw their Aquamarines overboard to calm the gods. Sailors were also said to have taken Aquamarine to sea as a lucky charm to protect against shipwreck, and many people today still wear Aquamarine to prevent travel sickness.

Back on shore, Aquamarine is believed to both soothe and prolong relationships, and for this reason is often given as an anniversary gift way before its official listing for one’s 19th anniversary. For those frightened of spiders or flying, wearing Aquamarine is said to suppress one’s phobias.

Out of the ground, many Aquamarines have a slight green tint and are often heat treated to turn the gem into a more pure blue.  However, over recent years, the lighter, natural colour has become very popular amongst gemstone collectors. In either shade, this birthstone for March is highly sought after for its clarity, transparency and undeniable calmness.

Similar to Amethyst where different shades are given different prefixes, Aquamarine also has a different prefix relating to its colour. Santa Maria Aquamarine describes those with a deeper shade of blue than normal. The name is derived from the Santa Maria de Itabira gem mines of Brazil, where deep and vibrant Aquamarines have been found - not, as some people believe, from the name of the ship on which Christopher Columbus made his first cross Atlantic voyage, or indeed from Santa Maria city in California.

The largest source of Aquamarine is found in the state of Minas Gerais in south-east Brazil, but today Africa is becoming a strong rival, with mining activities in countries such as Madagascar, Mozambique, Nigeria and Tanzania.

Aquamarine receives its colour from the presence of two types of iron, ferrous and ferric. Ferrous iron provides the gem with its trademark blue colour, whilst the presence of ferric iron turns the gem slightly green. Normally in its rough state, as when it is mined, Aquamarine is more of a greenish blue. To remove this secondary colour, the rough is normally heat treated before it is sent for cutting, converting ferric iron to ferrous iron. Unusually, as it does not take a high temperature to purify the colour of Aquamarines, it is undetectable in nearly all laboratory tests. For this reason it is always best to assume that any Aquamarine you purchase has been heat treated. As the heat treating does not intensify the tone of the Aquamarine (it only turns its green hues to blue) some gem collectors prefer Aquamarines that feature their natural greenish blue colour.

The darker an Aquamarine, the more desirable and valuable it becomes. Normally its tone ranges from just 10 to 30% tone and once into the high twenties it is often referred to as Santa Maria Aquamarine. Some Aquamarines will appear almost colourless in normal daylight and yet display a beautiful tone under the light of a candle or a light bulb; so much so that it is known as an evening gemstone.

Although today the prefix “Martha Rocha” is often used more to describe some of the finest Kunzites, it was initially used as a descriptive word for Aquamarine. In 1954 a huge glowing Aquamarine was discovered in the Brazilian town of Teofilo Otoni and was named after the winner of the Miss Brazil competition that year, whose eyes were said to have been of the same colour.

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A 195 ct Aquamarine on display in the The Genuine Gemstone Company museum.