The fresh bright color of aquamarine is so reminiscent of the ocean that its name derives from the Latin for “water of the sea.” Iron is
aquamarine’s coloring element, rendering a lively greenish-blue color when it is mined from the ground; however, aquamarine is most commonly heat-treated to eliminate the green component and emphasize the preferred blue color. This heat treatment is permanent and undetectable.
Both aquamarine and emerald belong to the beryl species. Unlike the closely related emerald, aquamarines can occur in large flawless crystals and are frequently faceted into larger sizes to maximize depth of color. Aquamarine forms very beautiful rough crystals that are hexagonal in outline, mimicking their internal structure. These rough crystals are collected by gem and mineral enthusiasts based upon locality or association with other minerals, as well as for the spectacular blue coloration. Major sources include Brazil, Nigeria, Zambia, Madagascar, United States (California, Maine, and North Carolina), Russia, and Mozambique.
The carving of gemstones is known as the glyptic arts, and aquamarines offer the perfect material for it because the crystals tend to occur in such large clean sizes. Chinese snuff bottles carved from aquamarine are some of the most rare and highly prized brands. Large rectangular step cut aquamarines were particularly popular in the Retro era (1941 - 1955), when big bold jewelry was the fashion. Aquamarine was well suited for pairing with rose gold during this period, and often was paired with small ruby accent stones in brooches, rings and pendants.
A large and important aquamarines carving bearing a portrait of Julia, daughter of Emperor Titus (40?-81 C.E.) resides in the Cabinet des Medailles in Paris, France, and measures 1³/₈ by 2 inches in diameter. This historical gem was once owned by Charlemagne (742-814 C.E.), King of the Franks and emperor of the Holy Roman Empire.
Variety: Aquamarine, cats’ eye aquamarine, star aquamarine
Chemical Composition: BeAlSiO2
Color: bluish-Green, greenish-Blue
Hardness: 7 ½ - 8
Crystal System: Hexagonal
Refractive Index: 1.577 - 1.583 (+/- 0.17)
Specific Gravity: 2.72 (+ .18, - .05)