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Roger Weller, geology instructor

Blue Beryl
by Kirstyn Clark
Physical Geology
Fall 2015

Greenish-Blue and Pure Blue Beryl (Aquamarine)

            Beryl that is greenish blue to pure blue is called Aquamarine named for its color being similar to sea water – aqua marine roughly means “water of the sea” when translated from Latin. It is one of the most common colors of Beryl, and can also be heat treated to change the color. For example, heat treatment could be used to permanently deepen an aquamarine's colors from greenish to sky blue. The blue color is known to be caused by the addition of Fe in the structure's “channels.” Differing amounts of Fe affect the color of the gem. Aquamarine is prized for its high hardness (7.5-8), and the gems that form in flawless crystal formations are still highly prized throughout the world despite blue topaz's rise in popularity.



An Aquamarine crystal example.

Photo credit to Roger Weller/Cochise College


            Greenish Blue and Pure Blue Beryl has the same chemical composition as other beryl types, Be3Al2Si6O18. It merely has differing amounts of Iron in it, giving it a blue color. Another type of beryl with a similar color would be Maxixe Beryl, which is of a light blue or dark blue color. It is sufficiently darker than Aquamarine's color, however. This green-blue color, so similar to the sea, earned it the reputation of a lucky stone for sailors, acknowledged even by the Greeks and Romans in the past.


            Aquamarine is more common than other varieties such as Bixbite because it is found in many places around the world. Such places are Brazil, India, China, the USA and Pakistan, among others. This Beryl material can range from flawless sky blue gemstones to duller non-gem quality stones, such as the picture below.



Blue Beryl/Aquamarine.

Photo credit to Roger Weller/Cochise College


            Aquamarine is commonly used in jewelry. Some prefer the deeper blue gemstones that sell for higher prices, however there are plenty of people who actually prefer the lighter, more transparent gems. This gem stone is suited for use in jewelry due to its lack of need for care, such as the treatment that emeralds need. Another difference from emeralds is the transparency of Aquamarine. Whereas emeralds are cloudy, the aquamarine variety of beryl tends to be much more crystal clear. Some of Aquamarine's beauty comes from its vitreous luster – where it shines similar to glass. Combined with its varying shades of blue, its high hardness, and the transparency of the finer gems, it is no wonder that this variety of beryl is so commonly used for jewelry.


A cut Aquamarine gem.

(Credit to Roger Weller)


            An additional fact about Aquamarine is that though it has been created in a laboratory, the cost of producing it is too high in comparison to how common the gem is. Therefore, synthetic Aquamarine is not sold on the market often.


Photo Credit to Roger Weller/Cochise College


Works Cited