Aquamarine, the birthstone for March, is a gemstone deeply connected to the ocean, evoking images of clear, tranquil waters. Its name, derived from the Latin “aqua marina” meaning seawater, reflects its captivating color range from pale blue to light greenish-blue hues. Historically revered for its protective qualities and believed to bring happiness and safe travels, aquamarine continues to be a cherished gem, admired for its beauty and symbolic significance. This article will delve into the history, geological origins, gemological properties, and cultural lore surrounding this fascinating gemstone.
History and Lore
The association of aquamarine with the sea dates back to ancient times. Greek legends claimed the gem was washing up on shores as protective charms for sailors, fostering a belief that it could calm stormy seas and ensure a safe voyage. Both Greeks and Romans utilized aquamarine as protection while traveling by water. This belief in its protective power extended beyond seafaring; it was considered a sacred gift from mermaids, further solidifying its connection to the marine world.
Ancient Romans also attributed healing properties to aquamarine, noting its near invisibility when submerged in water. The Egyptians, Greeks, Hebrews, and Sumerians all valued aquamarine, with stones engraved to represent the six tribes of Israel believed to be worn by the High Priest of the Second Temple. Greeks as far back as 2000 years ago were engraving designs into aquamarine, creating intaglios.
Beyond its maritime associations, aquamarine has historically been seen as a symbol of youth and happiness. It was believed to bring happiness in marriage and, in battle or litigation, to make the wearer unconquerable and amiable, quickening the intellect. More recently, aquamarine is traditionally given as a gift on the 19th wedding anniversary.
Geological Formation and Sources
Aquamarine is a variety of the mineral beryl, a beryllium aluminum silicate with the chemical formula Be3Al2(Si16O18). Beryl crystallizes in the hexagonal system and is known for forming long, six-sided columns. The gem’s color is intensified by the size of the crystal, with larger stones often exhibiting more vibrant hues.
Aquamarine is found in a variety of locations worldwide, including Afghanistan, China, Kenya, Pakistan, Russia, Mozambique, the United States, Brazil, Nigeria, Madagascar, Zambia, Tanzania, Sri Lanka, Malawi, India, Zimbabwe, Australia, Myanmar, and Namibia. However, the Brazilian state of Minas Gerais has been a particularly significant source for the past two centuries. Within Minas Gerais, aquamarines are found in both primary (hard rock) and secondary (weathered) pegmatite deposits, particularly near the gem center of Teófilo Otoni. Some sources in Africa also produce gems with stronger than typical saturations, even in smaller sizes.
Gemological Properties
Aquamarine possesses a hardness ranging from 7.5 to 8 on the Mohs scale, making it a durable gemstone suitable for various jewelry applications. It exhibits an imperfect cleavage and a vitreous luster. Optically, it is uniaxial negative, and some specimens may display strong dichroism, meaning they show different colors when viewed from different angles.
The refractive index of aquamarine ranges from approximately 1.57-1.58 to 1.58-1.59. It is a pleochroic gem, meaning its color appears different depending on the direction in which it is viewed. When looking at a crystal column one way, it can appear almost colorless, but when rotated lengthwise, the darker blue colors become apparent. This property is advantageous for cutters, allowing them to orient the stone to maximize color display.
Inclusions commonly found in aquamarine include mica, hematite, and liquid-filled tubes and hoses. These liquid inclusions can expand considerably if the crystal is overheated, potentially causing fractures or, in rare instances, even explosion.
Aquamarine’s color ranges from pale blues to light blues to yellowish blues. While some stones can achieve colors comparable to sapphire, it is generally much lighter in tone. Stones weighing at least five carats are typically needed to achieve the best, most intense blue and green hues.
Symbolism and Metaphysical Beliefs
Throughout history, aquamarine has been imbued with symbolic meaning. Its name and color have consistently linked it to the sea, representing tranquility, clarity, and emotional balance. It is believed to be a powerfully soothing influence on relationships, making it a popular gift.
Ancient beliefs attributed various powers to aquamarine, including protection against foes in battle and litigation, and the ability to promote happiness and marital harmony. It was thought to bestow courage, dispel fear, and enhance intellectual abilities. The gem was also considered to purify the spirit and soul.
Care and Cleaning
Due to its relatively high hardness, aquamarine is a durable gemstone. However, care should be taken to avoid subjecting it to sudden temperature changes or harsh impacts, as this could potentially damage stones containing liquid inclusions.
Cleaning aquamarine jewelry is generally straightforward. It can be safely cleaned with warm, soapy water and a soft brush. Avoid ultrasonic cleaners, as the vibrations could potentially affect stones with inclusions. After cleaning, rinse thoroughly with clean water and dry with a soft cloth.
Market Value and Notable Specimens
The value of aquamarine is determined by hue, tone, and saturation, with pure blue or blue with slight hints of green, paired with moderately strong saturation and medium-dark tone, being the most valuable. While bluer gems are often preferred, stones exhibiting both blue and green hues may remain untreated due to a market preference for the “seawater” color.
Interestingly, faceted aquamarine gems weighing more than 25 carats may actually lose value, as jewelers may find them impractical for use in jewelry. This is due to the high percentage of usable gem-quality material found in many aquamarine crystals, leading to the production of exceptionally large stones.
Notable aquamarine specimens include the Dom Pedro Aquamarine, believed to be the largest faceted aquamarine in the world, weighing 10,363 carats. Fashioned into a 14-inch obelisk by Berndt Munsteiner using the fantasy cut technique, it is a celebrated attraction at the Smithsonian Institution. Another significant specimen is the 1,298-carat dark blue rectangular step-cut aquamarine presented to First Lady Eleanor Roosevelt by the Brazilian government in 1936, now housed at the Franklin D. Roosevelt Presidential Library and Museum.
Conclusion
Aquamarine, the captivating birthstone of March, holds a rich history and enduring appeal. From its ancient associations with the sea and its protective powers to its modern symbolism of tranquility and clarity, this gemstone continues to enchant and inspire. Its geological origins, unique gemological properties, and stunning color variations make it a prized possession for gemstone enthusiasts and a beautiful addition to any jewelry collection. The gem’s durability and relative abundance contribute to its accessibility, while exceptional specimens like the Dom Pedro Aquamarine demonstrate the breathtaking potential of this remarkable gem.