Almost nobody asks me anything about aquamarine. They look at the color, they like it, and they buy it. I have been cutting natural stone since 2019, and this is the stone I have been asked the fewest questions about.
It is the opposite of obsidian, where almost everyone asks me whether their stone is real.
That silence is why this article exists. There is one thing about that blue color that almost nobody tells a buyer. It is not bad news. It is simply something you should know before you buy.
Aquamarine meaning, in one paragraph
Aquamarine is associated with calm, clarity and the sea, and it was traditionally worn as a protective stone.
It is also the birthstone for March.
That is the short version. Below I explain where each of those meanings comes from, and which of them are actually written down anywhere.
Where the name comes from
GIA puts it plainly: "The name 'aquamarine' is derived from two Latin words: aqua, meaning 'water,' and marina, meaning 'of the sea.'"
The name describes the color, not a property. It is the most reliable meaning this stone has.
Tradition versus documented history
A lot of what you read online about this stone is repeated so often that it starts to sound like fact. Much of it is not.
What the sources actually say. The American Gem Society writes that "it was once believed that this gemstone would protect sailors and guarantee a safe voyage," and that "ancient Romans would carve a frog into the gem to help turn enemies into friends."
GIA is more careful, and speaks about beryl as a whole rather than aquamarine specifically. It records the belief that the mineral "gives the wearer protection against foes in battle or litigation", meaning in a fight or in a court case, and that it "makes the wearer unconquerable and amiable, and also quickens the intellect."
What no source says. Neither GIA nor the American Gem Society names a specific ancient text or period for the sailor story. It is recorded as tradition, not as dated historical fact.
I point this out because the difference matters. A beautiful tradition and a documented history are not the same thing, and I would rather not present one as the other.
Modern meanings are beliefs
In modern use, aquamarine is associated with calm, clear communication and courage.
Let me be direct about this. These are beliefs, not measured properties. I cut stone for a living, I am not a doctor, and I will not tell you that this stone heals anything.
If the color calms you, that is real, and it is reason enough to wear it. I will not promise you more than that.
Aquamarine is blue beryl
Aquamarine is not a mineral of its own. It is the blue variety of beryl, the same mineral whose green variety is emerald.
Measured properties:
| Mineral | Beryl |
| Chemical formula | Be3Al2Si6O18 |
| Hardness, how well it resists scratches | 7.5 to 8 on the Mohs scale |
| Refractive index, how much it bends light | 1.577 to 1.583 |
| Specific gravity, how heavy it is for its size | 2.72 |
| Weak direction | None that matters, which is good news for a ring |
| Cause of color | Ferrous iron |
That hardness figure means something in practice. Aquamarine is one of the harder materials I work with.
Obsidian sits at 5 to 5.5 and malachite at 3.5 to 4. Aquamarine stands up to daily wear far better than either.
Where the blue comes from
The International Gem Society is specific: "This beautiful gem receives its coloring from trace amounts of ferrous iron."
Blue is not one recipe. Lapis lazuli gets its blue from a different mineral, lazurite. Light barely gets through it, where aquamarine is clear. I wrote about what lapis lazuli actually is, and the four checks for a fake one.
So the blue comes from chemistry, not from treatment. But where nature stops and the furnace begins is the subject of the next section.
Heat treatment: what sellers leave out
Let me say this before I say anything else.
My aquamarine is heat treated. It arrives at my bench already blue. I do not heat it myself. The heating happens before it reaches me.
This is not a fake stone, and it is not something unusual about my material. GIA states that "most of the aquamarine in the market was heat-treated to give it more of a pure blue."
IGS explains what actually happens: "Most aquamarines come out of the ground with a greenish tint, but this will disappear after heating to 375° C, which leaves a pure blue color."
Nobody can check it afterwards
And here is the part that matters most. IGS writes that "distinguishing this heating process proves impossible. Therefore, gem graders should describe any pure blue aquamarines as 'probably heat treated.'" A gem grader is the person who writes the description a stone is sold under.
So nobody can establish it afterwards. Not you, not me, and not a laboratory either, because the heating leaves nothing behind to find.
What this means for you
- The color is permanent. GIA: "Heat treatments in all of the gemstones mentioned above are considered durable and permanent under normal handling conditions."
- The stone is still natural. It is not synthetic and it is not an imitation.
- It has little effect on value, precisely because most of the market is the same.
I tell you this because you could never find it out on your own. If someone sells you a pure blue aquamarine and assures you it is definitely untreated, they either do not know, or they are not telling you the truth.
I take the same line with every stone on this site. Our article on labradorite explains why a gray labradorite is usually a cutting decision rather than a fake.
The color range
Aquamarine ranges from a pale greenish blue to a deeper blue. GIA describes the most valued color as "a dark blue to slightly greenish blue with moderately strong intensity."
One practical note for shopping. IGS writes that you will "rarely see aquamarines darker than a Swiss blue topaz", which is the bright, strong blue you have seen in shop windows.
When a stone looks unusually dark, that is usually the work of the cut rather than the color of the stone itself. So if someone offers you a very dark blue stone as aquamarine at a very low price, it is worth pausing.
How to tell aquamarine from blue topaz
These two stones look alike, and they are confused often.
| Aquamarine | Blue topaz | |
| Hardness | 7.5 to 8 | 8 |
| Specific gravity | 2.72 | about 3.5 |
| Depth of color | Rarely very dark | Often much darker |
The most practical difference is weight. Blue topaz is noticeably heavier than aquamarine at the same size. You can feel it in your hand.
An honest limit: that is what you can notice yourself. Telling the two apart for certain is laboratory work, where those two numbers are measured precisely.
That is a different question from the heat treatment above. A laboratory can say which mineral you have. It cannot say whether the stone was heated.
Why our aquamarine is raw
Every piece in our aquamarine collection is raw. We give the stone its shape and stop before the polish.
The difference worth knowing is shine. A polished stone glows from one smooth surface. A raw one keeps the crystal's own face. On some of ours that face carries fine parallel lines, and the light travels along them. On others it is clouded, with white drifting through the blue. Either way the color is never even: it gathers deeper in some places and fades to near white in others.
A polish would flatten all of that into one color. We keep it.
How to care for aquamarine
There are two specific warnings here, and most articles carry neither.
The first is about inclusions, the small marks and threads sealed inside a natural stone. IGS warns that "inclusions within aquamarines may not react well to mechanical cleaning techniques like ultrasound or steam."
From my own bench: when I cut aquamarine I see inclusions most of the time. Fine fractures and thread-like inclusions are normal in this stone. I have had pieces that came out completely clean, but that is the exception, not the rule.
The second is about the heat treatment itself. GIA notes that "submitting gemstones to intense heat may render them slightly more brittle than usual, and care must be taken not to damage pointed faceted corners and edges."
Facets are the flat faces cut onto a stone. Where two of them meet, the stone is at its thinnest, and that is the part a knock finds first.
What I would do:
- Do not use ultrasonic or steam cleaners
- Use a soft brush, warm water and mild soap
- Store it separately from harder stones
- Avoid knocks on the cut corners and edges
How we work with aquamarine at Akra
Our aquamarine comes from Brazil. GIA notes that Brazil is historically one of the main sources for this stone: the largest Brazilian aquamarine on record was found in 1910 in Minas Gerais and weighed 110 kilograms.
I make every piece from scratch: the design, the cutting of the stone, and the setting in 925 sterling silver, at our workshop in Tbilisi.
Aquamarine asks for time. It is harder than most of the stones I work with, so it cuts more slowly. Shaping it and preparing it for the setting is a separate job again, and slower still. It is not a stone you rush.
A pair asks for twice that, because two stones have to hold the same blue before either is set. Those go into raw aquamarine earrings.
See the aquamarine pendant we cut and set by hand, or look through the other raw aquamarine necklaces.
Quick answers
Is aquamarine a precious stone?
It is beryl, the same mineral family as emerald. Its value depends on color, clarity, size and the quality of the cut, not on the name alone.
Is aquamarine good for everyday wear?
Yes. At 7.5 to 8 on the Mohs scale it is hard enough for daily wear. That matters most on a hand, which meets more than any other piece, and it is why we set it into raw aquamarine rings. Still store it separately from harder stones.
Is my aquamarine heat treated?
If it is a pure blue, most likely yes. GIA states that most of the aquamarine on the market has been heat treated, and IGS states that the process cannot be detected afterwards. It does not make the stone less natural or less valuable.
Why is some aquamarine greenish?
Because natural aquamarine often comes out of the ground with a greenish tint. A pure blue is usually the result of heating.
What month is aquamarine the birthstone for?
March. If it is a gift, my guide on how to choose jewelry for someone else may help.
