Question: Emeralds and aquamarines are both beryls. Emeralds are green beryls; aquamarines are blue to blueish green beryls. Since emeralds are so fragile and sensitive, does this mean aquamarines make poor jewelry stones?
By International Gem Society 3 minute read
aquamarine round

Round aquamarine. Photo © International Gem Society.

Answer: Aquamarines are relatively tough gems. Nevertheless, this popular jewelry stone does have some vulnerabilities. Let’s take a look at aquamarine durability and the potential problems that jewelers, faceters, and consumers should bear in mind.

emeralds and aquamarines on display

Although both emeralds and aquamarines belong to the beryl family, emeralds have a greater tendency to fracture because of how they form. The trace elements that give them their green color — chromium and vanadium — also weaken their crystal structure. Aquamarines, on the other hand, get their blue to blueish green color from traces of iron. Emeralds and aquamarines on display. Photo by Mauro Cateb. Licensed under CC By 2.0.

Aquamarine Hardness

Aquamarines have a hardness value of 7.5 to 8 on the Mohs scale. That means these gems have excellent resistance to scratches and abrasions. They can’t be scratched by anything with a lower hardness. Since household dust only has a hardness of 7, it can’t damage aquamarines. This makes them good choices for daily wear jewelry, like engagement rings. Aquamarine’s relatively high hardness also means it can retain a good polish for a long time.

Aquamarine Toughness and Cut Styles

Hardness isn’t the only measure of aquamarine durability. Aquamarines also have imperfect cleavage. That means if they’re struck along an internal cleavage plane they could split in two. Like most gems, aquamarines have “Brittle” tenacity. That means they’re prone to breaking or chipping if struck.

aquamarine and diamond platinum ring by Tiffany & Co.

Like many gems, aquamarines show conchoidal, “shell-like” fractures when broken or chipped. The oval-shaped aquamarine in this Tiffany & Co. platinum ring shows a conchoidal fracture on its edge. Photo courtesy of liveauctioneers.com and Fellows.

Despite these vulnerabilities, aquamarines still have “Good” toughness. However, some precautions are in order when cutting and setting these gems. Since the corners of gems are most vulnerable to breakage, faceters frequently select round, oval, or cut-cornered styles (like an emerald cut) for aquamarines. Cut aquamarines with corners or thin girdles should have protective settings in jewelry.

broken heart-shaped aquamarine

Heart-cut aquamarine gem with noticeable breakage. Photo © International Gem Society.

Aquamarine Durability and Gemstone Maintenance

Aquamarines have fair resistance to heat. Steam jewelry cleaners that operate below 700° F (371° C) usually won’t harm these gems, as long as they don’t have liquid inclusions or internal fractures. These might expand during heating and crack the gemstone.

Exposing aquamarines to temperatures of 700-850° F (371-454° C) may cause other problems, even if the stones don’t shatter. These temperatures may cause aquamarines to change color. Higher temperatures, such as those created by a jeweler’s torch, may result in discoloration. Before repairing metal jewelry, jewelers should remove any aquamarines from their settings as a precaution.

Broken briolette-shaped aquamarine. Photo © International Gem Society.

Aquamarines can handle many chemicals used for cleaning, from soapy water to moderately strong acids. However, hydrofluoric acid, found in home rust removers and strong cleaners, can damage them.

Ultrasonic jewelry cleaners, including their solution baths, are usually safe for aquamarines, but the vibrations generated by the device could damage stones with liquid inclusions or fractures.

If you don’t know if your aquamarines have any such inclusions, clean them with a soft brush, mild detergent, and warm water. Consult our gemstone jewelry care guide for more recommendations.

Aquamarines and Light Exposure

Both mined and lab-created aquamarines are stable under all light sources, including sunlight, artificial indoor lighting, and ultraviolet, even for prolonged periods. However, so-called Maxixe aquamarines (irradiated blue beryls) will fade over time when exposed to light.

Maxixe beryls

Maxixe beryl cabochons, 28.8 and 29.13 cts. Photo courtesy of liveauctioneers.com and Itineris.