Aquamarine Value, Price, and Jewelry Information
Named after the color of sea water, aquamarine is the blue to blue-green member of the beryl family. Readily available and moderately priced, the modern March birthstone makes an excellent jewelry stone.
Since aquamarines are available in large sizes, there's no incremental increase in value per carat for large gems. A 50-ct aquamarine will be worth the same price per carat as a single carat gem of equal quality. The gem price is dependent on clarity, depth of color, and to a lesser extent the purity of color.
For more detailed information on aquamarine quality factors, consult our aquamarine buying guide.
The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.
|Is a Variety of||Beryl|
|Colors||Blue to blue-green.|
|Fracture||Conchoidal to uneven|
|Hardness||7.5 - 8|
|Enhancements||May be heat treated to remove green tint. Very common, undetectable.|
|Transparency||Opaque to transparent.|
|Absorption Spectrum||Natural aquamarine: a broad band at 4270 and a diffuse band at 4560. (Weak band may be seen at 5370). Maxixe aquamarine: a narrow line at 6950, a strong line at 6540 and weak lines at 6280, 6150, 5500 and 5810.|
|Phenomena||Chatoyancy; asterism (rare).|
|Formula||Be3Al2Si6O18 + Fe|
|Pleochroism||Natural aquamarine: blue/colorless (sometimes greenish). Maxixe aquamarine: non-pleochroic (blue/blue).|
|Optics||o = 1.567-1.583; e = 1.572-1.590; Uniaxial (-).|
|Etymology||From the Latin aqua marina for "sea water," in allusion to the color.|
|Occurrence||Granitic rocks, especially granite pegmatites.|
|Inclusions||Long, hollow tubes, negative crystals, chrysanthemums. 2-phase and 3-phase inclusions. See "Identifying Characteristics" below.|
This beautiful gem receives its coloring from trace amounts of ferrous iron. Its hues range can range from blue-green to deep blue, and its tones can vary from very light to moderately dark. You’ll rarely see aquamarines darker than a Swiss blue topaz. When you do, the color is usually enhanced by the cut.
Due to aquamarine’s color and name, in Western cultures, this gem has a folklore strongly connected to the sea. Its mystical purview traditionally includes protection for sailors and fishermen as well as travelers in general.
Gem Cutting Recommendations
When cutting aquamarine, the primary consideration should be depth of color. Deep designs, like Barions and emerald cuts, are usually preferred. Faceters should use 43° pavilion mains on aquamarine for the highest brilliance. Low crown angles will produce higher brilliance, but higher crowns are often used to deepen the color.
The beryl family, including aquamarines, are some of the easiest gems to polish. Diamond polish is the most common method. A high-quality polish can give light aquamarines such great brilliance they might be confused with higher refractive index (RI) gems. Even with a moderate dispersion of 0.014, light stones with high crown angles will show their spectral colors well. This makes for an outstanding gemstone.
While the highest values go to the richer colors, a well-cut light aquamarine can be one of the most spectacular examples of gem faceting in the world.
Three-piece aquamarine rough and cut set. Crystal specimen, 9.7 x 5.0 x 3.8 cm; Portuguese round brilliant cut, 18.47 mm and 32.65 cts; Cat’s eye round cabochon, 10.66 mm and 4.81 cts. Chumar Bakhoor, Hunza Valley, Gilgit District, Gilgit-Baltistan (Northern Areas), Pakistan. © Rob Lavinsky, www.iRocks.com. Used with permission.
Inclusions are interesting features of this gemstone. Beryl, and aquamarine in particular, are known for having long, hollow tubes. This distinctive feature will identify a gem as a member of the beryl family.
Aquamarines may have transparent and metallic inclusions, such as biotite, hematite, ilmenite, phlogopite, pyrite, and rutile in skeletal crystals. They may also contain crystals of apatite, cassiterite, epidote, garnet, muscovite; quartz, and tourmaline. Some stones contain “snow-stars,” irregularly shaped liquid droplets in a star formation. The Martha Rocha aquamarine has notable “snow-star” inclusions.
Cat’s Eyes and Star Stones
With enough hollow tube inclusions and proper cutting, aquamarines can show chatoyancy and even asterism. Collectors prize beautiful cat’s eye aquamarines very highly. Their prices come very close to that of clean, faceted gems with the same coloring. Star aquamarines are even more rare than cat’s eyes and can command premium prices.
Most aquamarines come out of the ground with a greenish tint. However, this will disappear after heating to 375° C, which leaves a pure blue color. Removing aquamarine’s green tinting through heat treatment is very common. In the past, this was done routinely. Nowadays, a more sophisticated public has started appreciating slightly green, untreated aquamarines. However, distinguishing this heating process proves impossible. Therefore, gem graders should describe any pure blue aquamarines as “probably heat treated.”
In the 1970s, Maxixe (pronounced mah-SHE-she), a very dark blue aquamarine, appeared on the market. However, the color of this irradiated product isn’t stable. Although these stones have mostly disappeared from the market, if you’re ever offered a very deep blue aquamarine, buyer beware.
You can distinguish the Maxixe from a natural aquamarine by its lack of pleochroism. Natural aquamarines have distinct blue and colorless dichroism. On the other hand, the Maxixe has no pleochroism. When viewed from any angle, it just shows blue. The absorption spectrum of natural aquamarine and the Maxixe also differs. With a spectroscope, you’ll see a narrow line at 6950, a strong line at 6540, and weak lines at 6280, 6150, 5500, and 5810. This differs considerably from natural aquamarine’s spectrum, with a broad band at 4270 and a diffuse band at 4560.
You can also distinguish a Maxixe aquamarine from a natural stone with a dichroscope. Both windows remain blue when viewing a Maxixe. In contrast, one window should be colorless or pale yellowish when viewing an untreated specimen.
Brazil is the world’s major source of fine aquamarine gems. Localities include Minas Gerais, Rio Grande do Norte, Ceara, and others.
Madagascar has more than 50 specific localities that produce fine, blue gem material.
Other notable sources include the following:
- United States: San Diego County, California (not much gem material); Mt. Antero, Colorado; Connecticut (some gem); Maine; North Carolina.
- Australia: Mt. Surprise, North Queensland (small).
- India: Karur, Madras, and Kashmir (medium blue color).
- Namibia: Rossing (in pegmatites).
- Nigeria: Jos (abundant material, some fine color).
- Russia: Mursinsk mine (and other localities).
- Afghanistan; China; Mozambique; Myanmar; Pakistan; Sri Lanka; Vietnam; Zimbabwe.
You’ll find aquamarines available in a remarkable range of sizes. Lapidaries have cut gems that weigh several hundred carats, much too large to be worn. Beryl crystals weighing many tons have been found in pegmatites, but these are never of gem quality. However, aquamarines may be very large and still be gem quality.
A blue-green crystal was found in Marambia, Teofilo Otoni, Brazil. This irregular prism, transparent end to end, measured 19 inches long and 16 inches across and weighed almost 243 pounds.
The famous Martha Rocha aquamarine, found in Brazil, weighed 134 pounds and yielded more than 300,000 carats of superb blue gems. An even larger crystal found in 1910 weighed 229 pounds but yielded only 200,000 carats of cut gems.
- British Museum (Natural History) (London England): 67.35 (blue) and 60.90 (greenish); 879 (sea-green, oval).
- American Museum of Natural History (New York): 272, 215, and 160; also 355 (Sri Lanka), 144.5 (Brazil).
- Hyde Park Museum, New York: 1847 carats.
- Smithsonian Institution (Washington, DC): 1,000 (blue-green, fine color, Brazil); 911 (blue, Brazil); 263.5 (blue, USSR); 71.2 (pale blue, Sri Lanka); 66.3 (pale blue-green, Maine); 20.7 (pale blue, Madagascar); 15.3 (blue-green, Idaho); 14.3 (blue, Connecticut).
- Brazilian aquamarine: bluish green, (also a misnomer for bluish green topaz).
- Madagascar aquamarine: fine, medium blue.
- Maxixe beryl: treated beryl with excellent aquamarine blue, known for fading. Also called halbanite.
Please note, don’t assume aquamarines billed as “Brazilian” or “Madagascar” actually come from these sources. These terms may only refer to the color. Ask to see documentation to certify a gem’s origin.
Aquamarines require no special care. They can resist the rigors of everyday wear very well. However, inclusions within aquamarines may not react well to mechanical cleaning techniques like ultrasound or steam, increasing the risk of shattering. Consult with a gemologist first to determine if your gems can withstand these cleaning methods. Of course, you can always use a soft brush, mild detergent, and warm water to clean your aquamarines safely. Consult our gemstone jewelry care guide for more recommendations.