The Beryl Gem With the Color of the Sea - Aquamarine

By Chris Ralph

Aquamarine, the "gem of the sea", does not come from the ocean, but derives its name from from the color of "sea water". The reference is obvious: aqua sparkles like the sea and its color is pale to medium blue, sometimes trending to a light green color. Aquamarine is the birthstone for March. Aquamarine is always a pastel blue to blue green, but the darker the color, the more valued it is. Many folks prefer a pure blue, with no green in it, however the greenish colors are also very beautiful.

It is a relatively hard gemstone, 8 on the Mohs scale, and possesses moderate brilliance. Because the color is generally pale, larger stones show their color best. Aquamarine should also have a good clarity. If you are looking for a big, durable gemstone, aqua is readily available in larger sizes and is truly dramatic when cut in rectangular or oval shapes. These stones are also often cut in emerald or step cuts. More saturated colors are unusual in small sizes: usually it takes a stone of some size for the color to appear as a darker shade. Aquamarine is a durable and lively gemstone that is appropriate for all jewelry uses. Its pale fire is flattering to most skin tones.

Aquamarine can occur in very large clean hexagonal crystals, and are even found as bi-colors with other beryl minerals such as morganite. The coloring element to produce the beautiful blue green color is iron, which is substituted for aluminum in the crystal structure. The gem forms special in geological formations known as pegmatites. Most of the best and largest crystals form in open vugs, also known as pockets, associated with crystals of quartz and feldspar.

Aquamarine is found in Brazil, Zambia, Mozambique, Angola, Nigeria, Afghanistan and other countries, but Brazil is overwhelmingly the major source.. The principal producer of aquamarine has been Brazil but in more recent times Zambia, Mozambique and Nigeria have been producing very fine quality stones. Some very dark blue aquamarine is also being mined in India. The largest high quality gem crystal ever discovered, mined in the early 1900's, was a 200-kilogram crystal found in Brazil. It was so clean that one could read newsprint through it! Some Aquamarine continues to be produced in smaller quantities, but it has been years since large quantities have come to the market.

This gemstone has been popular for centuries, but received new vigor during the early 1970's. As a result, the price has remained stable or has increased even during recessionary times.
Twenty years ago the demand for aqua was small, and the material was quite inexpensive.
Today the finest gems may wholesale for well over $1,000 per carat. Fine quality aquamarine in sizes over 10 carats is not abundant. Commercial stones tend to be pale blue or pale blue-green, while investment-grade material is deeper blue, and of a medium to dark tone. The pervasive demand for aquamarine in the jewelry marketplace, however, indicates that all grades can ultimately be used for adornment and provides an excellent secondary market potential.

Intensity of color and clarity are the most essential considerations in evaluating Aquamarine.
Aquamarine of pale colors is most commonly seen in commercial jewelry stores, but stones of a good deep blue color are considered far more valuable than the pale ones. It should posses at least a bright sky blue color at a minimum. Exceptionally deep and vivid blue, to blue green colors are very scarce and becoming increasingly valuable. As part of the normal finishing process, many aquamarines are heated to remove traces of yellow and permanently intensify the blue color. Some aquamarine occurs in a blue/green color and even a pure green color, these are sometimes heat-treated to a temperature of 600-1200 degrees Fahrenheit to produce a pure blue color. This treatment is permanent and accepted in the trade as standard. All gem quality aquamarine should be well-cut and free of any inclusions.

For photos and more information on the varieties of aquamarine gems, see the author’s website at: http://nevada-outback-gems.com/Encyclopedia_pages/Aquamarine.htm

The author has an entire set of web pages which are devoted to providing information about the world of gemstones. His gemstone information Encyclopedia page can be seen at:
http://nevada-outback-gems.com/Encyclopedia_pages/Gemstone_Encyclopedia.htm

Chris Ralph writes on small scale mining and prospecting for the ICMJ Mining Journal. He is a rock hound and prospector and owns his own turquoise mines in Nevada. His website on gemstones and jewelry can be viewed at: http://nevada-outback-gems.com