Cumaru Aquamarine is a beautiful bluish-green gemstone from Cumaru do Norte in the northern Brazilian state of Pará. Aptly exhibiting this gem’s oceanic air, Cumaru Aquamarine’s rare color combined with its high transparency, brilliance and durability, makes for a highly desirable gemstone.
Hardness 7.5 - 8
Refractive Index 1.562 – 1.602
Relative Density 2.71 – 2.90
Related to Emerald and Golden Beryl, Cumaru Aquamarine is named for its locality. This incredibly rare gemstone melds a splash of green with cool blues, resulting in a uniquely colored Aquamarine that aptly exhibits this gem’s oceanic air.
This beautiful hue is extremely rare and a critical value determinant in a gem where color is the most important consideration. Cumaru Aquamarine’s striking sea foam blue radiates regardless of eye color or complexion, and is markedly different to Aquamarine’s more typical pastel and deep blues, making the gem highly desirable.
Unlike Emeralds, Aquamarine typically has a high clarity and transparency, making expert cutting that accentuates color critical. Faceted in the gemstone trading town of Governador Valadares by some of Brazil’s best lapidaries, Cumaru Aquamarine is finished eye-clean, the highest quality clarity grade for colored gemstones, displaying a desirable even color, good brilliance and excellent scintillation (play of light).
Coined by the Romans over 2,000 years ago, Aquamarine literally means ‘water of the sea’ in Latin, from the words ‘aqua’ (water) and ‘marina’ (sea). March’s birthstone, Aquamarine is a member of the Beryl mineral family (from the ancient Greek ‘beryllos’, meaning blue-green stone), commonly known as the ‘mother of gemstones’ because of its highly regarded gem varieties. Pure Beryl is colorless and trace amounts of elements are responsible for producing Beryl’s wonderful colors. Apart from Aquamarine blues, other Beryl gemstones include, Bixbite reds, Emerald greens, Golden Beryl yellows, Goshenite whites (colorless), Heliodor greenish-yellows, and Morganite pinks.
Ranging in color from pastel to intense deep blues, sometimes with splashes of green, Aquamarine is colored by trace amounts of iron. Since the early 1800s, Brazil has been a major source of fine Aquamarine.
Recently, a new pocket of Aquamarine was discovered in a remote region of the municipality of Cumaru do Norte in the state of Pará in northern Brazil. Pará’s most famous icons are the Amazon River and rainforest. Unfortunately, this gem’s discovery was limited to only one raw crystal. Ostensibly large at 200 kilograms, most of the crystal is not gem quality, resulting in an extremely limited supply. Cumaru Aquamarine is currently unavailable on the open market, accentuating the rarity of this uniquely beautiful gemstone.
Durability & Care
Cumaru Aquamarine (Mohs’ Hardness: 7.5 – 8) is an excellent choice for everyday jewelry. Always store Cumaru Aquamarine carefully to avoid scuffs and scratches. Clean with gentle soap and lukewarm water, scrubbing behind the gem with a very soft toothbrush as necessary. After cleaning, pat dry with a soft towel or chamois cloth.