Aquamarine

aquamarine
Aquamarine is a gemstone of the beryl family. It gets its name from the Latin phrase aqua marina, meaning “water of the sea”. It is a blue stone that comes in shades varying from a pale sky-blue to a rich blue-green, depending on the iron content in each particular stone. It is one of the few stones that are commonly treated to alter the colour: the blue hues intensify when aquamarine is subjected to heat treatments because the green overtones are permanently erased (on South American material only). Extreme heat (upwards of 500°C) can cause discolouration. While this means that today’s idea of beautiful colours are not difficult to come by, it also means that jewellers are not able to perform many types of repairs requiring high temperatures on pieces containing aquamarine. The stones must be unset for the repairs, then reset after all work is completed.

Aquamarines have been successfully created in the laboratory but can easily be identified by even an amateur jeweller or gemologist, hence the resale value of synthetic gemstones is virtually zero. Aquamarine is noted as the birthstone for the month of March.

African Aquamarine

African stones are famous for their unique combination of two factors: small size and brilliant, deep blue-green colour. Before the African deposits were discovered in Kenya, it was a universally-held truth that small aquamarines (under 2 carats) simply did not occur in deep blues. The world’s experience with aquamarines was limited to Brazilian varieties: with very few exceptions, pale-coloured small stones were the rule.

Now, African stones are plentiful in the aquamarine market. It is mined predominantly in Kenya, Zimbabwe, Zambia and Nigeria. Some dealers still prefer Brazilian aqua for its pure blue colour, without green overtones: however, the prices and availability of African aquamarine contribute to its solid place in the jewellery world.

We’ve chosen not to carry African aqua because, unfortunately, the same morality from the diamond fields has invaded all gemstone deposits in all parts of Africa. We will not carry, or work on, any “Blood” gemstones.

Brazilian / Columbian Aquamarine

South American aquamarine, from Colombia and Brazil, is known for its colour saturation. European buyers have prized the stones from this area since their discovery and have taken most of the top quality pieces back to Europe. The few high quality pieces in the Western hemisphere have been retained by the countries in which they were found as national treasures. As a result, modern North American jewellers aren’t used to the kind of saturation that can be found with Brazilian/Columbian stones . But deep electric blue stones do occur, such as the ones found in the now gone Santa Maria deposit in Brazil.

The largest aquamarine of cuttable quality was found in 1910 in Marabaya, Minas Gerais (Brazil). It weighed 243lb, was 18″ long and 15.5″ in diameter and was cut into many stones with a total weight of over 100,000 ct. Unfortunately, few Brazilian/Columbian aquas boast deep colour saturation in small sizes. For this the market has been increasingly reliant on Africa. While deep-colour blue Topaz can be produced to imitate aquamarine almost at will by heat treating, the same process will not create deep-coloured aqua. Heating an aqua permanently removes common green overtones but does not deepen its colour. Interestingly, similar green overtones in many African aquas cannot be removed by heating in ovens, a distinct advantage for the Brazilian/Colombian variety.

Because of the popularity of the much less expensive Blue Topaz, Aquamarine has fallen in popularity. A Blue Topaz, virtually identical in size, colour and tone can cost as little as one tenth of the price of an Aquamarine. This has segregated the Aqua to the jewellery boxes of the true collectors and Museums. We have several fine Aquamarines in stock at all times. Come in and see some fine gems set in Gold and Platinum or chose from our selection of unset pieces.

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