The name ‘Aquamarine’ comes from the Latin for sea water and is used to describe types of the mineral Beryl, that are of a light green, greenish blue or blue hue. This colour is created by the presence of iron within the gemstone. Aquamarine crystals are formed in long prismatic shapes and can also be found as broken pieces, or as water worn pebbles. Aquamarine is the birthstone for the month of March.
Aquamarine ranks 7.5 on moh’s scale of hardness making it a practical, reasonably hard-wearing gemstone to have in your jewellery collection, however it must be handled with care and can be damaged if mistreated. To clean your Aquamarine use warm soapy water and a soft toothbrush, once brushed, dry your Aqua using a soft lint free cloth. Chemical products should not be put on an Aquamarine as damage can occur. If you have a jewellery box, your Aquamarine jewellery should not be put together with other pieces otherwise general abrasion to the stones surface can cause scratches and this should be avoided.
The first documented use of Aquamarine was by the Greeks from approximately 480-300BC. Aquamarine is said to give its wearer protection against foes in battle or litigation. Legend has it, that it is the treasure of mermaids, with the ability to keep sailors safe in their journeys across the ocean. Wearing Aquamarine is also said to make you unconquerable, and sharpen your mind.
The largest ever cut Aquamarine is known as the Dom Pedro, cut from a crystal which originally weighed approximately 45kg, mined in Brazil, it was cut in to an obelisk by legendary gemstone cutter, Bernd Munsteiner with a finished weight of 10,363 carats.
Generally, the most sought after colours of an Aquamarine are of a dark blue to greenish blue, and as such these stones are of a higher value. Gems which are above five carats in weight will have an even more striking appearance. The distribution of colour within a fine stone will be very even with little to no zoning. Less expensive Aquamarine gemstones tend to be of a very pale blue colour.
With Aquamarine, clean stones are quite common in fine qualities, and can be found in large carat weights. Most faceted Aquamarine will be free of eye visible inclusions. Inclusions that can be seen using a 10x lens will normally create a ‘rain’ like appearance. Stones that are more heavily included will generally be cut in to cabochon shapes.
An Aquamarine can be cut in to a variety of shapes. A cutter will often cut the material in to the shape that will create the greatest balance of intense colour, and high clarity. For this reason Emerald cuts are a very popular choice as the larger facets show off the even colour distribution and high clarity of the stone. Aquamarine has an optical property known as pleochroism, and as a result shows two colours along different crystal directions, these are near colourless to a strong blue. The blue colour is matched to the cutting orientation that will retain the most weight, and so the cutter will align the table facet parallel to the length of the rough crystal.
Aquamarine can be found in a variety of sizes, and very large stones are possible due to the large crystals that can be sourced. A large stone can make for a beautiful centerpiece in a ring or brooch, but also smaller sizes are very popular as either accent stones in a clasp or to create a stunning pair of earrings.
The most important locations and sources of gem quality Aquamarine are Brazil, Kenya, Madagascar, Myanmar, Namibia, Russia, Nigeria, Zambia, Sri Lanka and the USA.
It is commonly accepted that heat treatment has been used on Aquamarine to improve its colour. The stones are heated to a high temperature of between 600-1200 degrees, and this type of treatment is permanent.