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Cryolite Gemstone: Properties, Meanings, Value & More

冰晶石寶石：屬性、意義、價值等

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Cryolite is a rare, white or colorless halide-group mineral from Greenland. The mineral often resembles an ice block but is a collector’s curiosity item rather than a gemstone for jewelry. 

Despite its lack of adornment use, this stone has played a vital role in history. Were it not for cryolite, aluminum wouldn’t have become one of the most produced metals of the 1900s, helping to win wars and even make the first airplane fly!

Want to know more? Come along as we uncover the secrets behind cryolite uses, history, value, and more!

Image credit: Didier Descouens, Cryolite – topotype -Former collection of the Faculty of Pharmacy of Paris | Creative Commons Attribution-Share Alike 3.0 Unported license

What Is A Cryolite Stone?

Cryolite is related to the semi-precious gemstone fluorite. Scientists sometimes use fluorite to create synthetic cryolite. 

Natural cryolite can be colorless, white, yellow, purple, or black. Astrologers recommend it as a zodiac stone for air signs Gemini and Aquarius.

Cryolite has numerous industrial uses, like:

• Fireworks (makes them yellow)

• Glass (makes it white & opaque, historically popular for prosthetic eyes)

• Insecticide & pesticide

• Enamel & ceramics (filler in bonded abrasive & glazes)

However, the most significant use is in extracting aluminum. 

Cryolite Used for Extracting Aluminum

In the early 1800s, scientists used electrolysis on the aluminum-rich rock bauxite to separate the aluminum. Electrolysis involves melting the substance and running an electrical current through it.

Unfortunately, bauxite required extremely high temperatures to melt — too high to be done cost-effectively. 

However, adding molten cryolite lowers the melting point, increases conductivity, and aids in the separation (dissolving) process, making electrolysis for obtaining aluminum cheaper and more efficient.  

Cryolite Specifications & Characteristics

The cryolite formula is Na3AlF6, written as sodium aluminum fluoride or sodium hexafluoroaluminate. Aluminum makes up 13 percent of cryolite.

This mineral is in the halide group along with fluorite, sylvite, and halite. The minerals in this group are halogen salts, meaning salts created when sodium, fluoride, and/or hydrochloric acid react with a metal.

Cryolite usually forms granular masses. It can also form small prismatic crystals, though these are rarer. Various types of twinning are also common.

Other colors on the stone are almost always from mineral inclusions, like brassy yellow from pyrite or reddish-brown from sphalerite. 

Here are more cryolite mineral properties:

• Mohs hardness: 2.5-3

• Color: Usually colorless to white; Can be slightly brown, red, or yellow; Rarely purple, gray, or black

• Crystal structure: Monoclinic

• Luster: Vitreous (glassy) to greasy, pearly on [001]

• Transparency: Translucent; Rarely transparent

• Refractive index: 1.338-1.339

• Density: 2.95-3.00

• Cleavage: None, but parting in 3 directions (pseudo-cubic cleavage)

• Fracture: Uneven

• Streak: White

• Luminescence: Weak thermoluminescence (heat-induced glow); Sometimes fluorescence & phosphorescence - bright yellow in SW-UV & light yellow in LW-UV; Some Canadian specimens fluoresce light blue in SW-UV

One of cryolite’s most fascinating properties is its invisibility in water. 

At 1.338, cryolite’s refractive index is extremely close to that of water (1.333). Thus, submerging colorless cryolite in water will make it appear invisible, like it suddenly disappeared.

This magical occurrence played a role in the early cryolite crystal meaning. 

Cryolite Meaning & History

Long before its official discovery, Greenland cryolite was known among the native Inuits, who had nicknamed it “the ice that never melts.” 

Additionally, they believed cryolite’s mystical “disappearing” aspect in water meant misfortunes and stresses could simultaneously disappear with it. 

Today, cryolite symbolizes enlightenment, transformation, and spirituality. 

The name “cryolite” comes from the Greek cryos for “ice.” Reasoning differs on the basis — the icy appearance, the discovery in frigid Greenland, and the mineral’s ability to melt like frozen saltwater under a blowpipe have all been referenced. 

First Official Discovery

The first official description of cryolite came in 1799. Danish physician Peder Christian Abildgaard was in Ivittuut (then Ivigtut), Greenland, in 1798. He found a unique “white, spar-like” mineral and brought it back to Denmark. 

Abildgaard wrote a report on the new mineral, publishing it in the 1799 edition of General Journal of Chemistry (translated from German) and presenting it to the Danish Royal Society of Science as “cryolite” a few years later.

British engineers, led by J.W. Taylor, started mining operations in Ivittuut that same year but sought out lead and silver. This was a fruitful but short-lived effort. 

Image credit: Image from page 36 of "Cranberries; : the national cranberry magazine" (1936) | Publisher: Portland, CT [etc. ] : Taylor Pub. Co. [etc. ]

Rise of Cryolite for Aluminum

At first, cryolite was only a minor source of aluminum and a material for creating sodium hydroxide (caustic soda). But almost a century after its discovery, cryolite finally gained significant use. What was cryolite used for? Extracting aluminum!

Two chemists, Charles Martin and Paul Héroult, happened to simultaneously (but separately) discover cryolite’s benefits as a flux for extracting aluminum in 1886. Called the Hall–Héroult process, this discovery made cryolite indispensable. 

Once a rare, expensive metal, aluminum became cheaper and more available than ever. Beyond basic household items, the most notable use was in airplanes, as aluminum metals were durable but lightweight.

After the Wright Brothers made their famous 1903 flight — on a largely aluminum aircraft — the metal became invaluable in aviation, gaining the nickname “the winged metal.” 

Cryolite for aluminum extraction was so valuable, the US military put Ivittuut’s mine under strict guard during WWII to protect the aircraft material from Germany.

Synthetic Cryolite and Mineral Depletion

As aluminum demand grew, it became clear natural cryolite wouldn’t keep up, so scientists started trying to synthesize it. In 1933, Soviet scientists figured out how to make synthetic cryolite, allowing it to remain prevalent in industrial use. 

Mining continued in the Greenland deposit until 1987, when its commercial supply was depleted. From 1960 on, the last of the cryolite went toward the newly established Air Greenland airline. 

Just as (natural) cryolite went from a revolutionary material to virtually extinct, Ivittuut went from the most significant cryolite mine in the world to an abandoned ghost town.

Luckily, we still have abundant synthetic cryolite today, and you don’t need to be in aviation to use this crystal for healing!

Image credit: Ra'ike | GNU Free Documentation License

Cryolite Healing Properties

Both synthetic and natural crystals can function as healing stones.

Cryolite possesses the qualities of other white gemstones, believed to emit purifying energies that promote balance and spirituality. Indeed, it’s touted as a “high-vibration” crystal, meaning its power is strong enough to sense immediately. 

So, what are the cryolite healing properties?

Physical Healing

Some purported physical cryolite crystal benefits include helping speech impediments and regulating bodily functions. It’s also said to stimulate the brain, making learning easier for those who struggle with understanding or retaining information.

Emotional Healing

Cryolite is said to help you overcome fear by discovering your true self and embracing your strengths. Crystal healers use it for increasing self-awareness, boosting creativity, and dispelling habits or beliefs that no longer serve you. 

Chakra Healing

All crystals can function as chakra stones targeting a blocked energy center (chakra) to resolve negative side effects. Cryolite is particularly effective for the third eye chakra. 

The third eye, located in the middle of your forehead, governs intuition and spiritual wisdom. When it’s blocked, you may lack concentration and direction. Using cryolite to open the chakra can bring you purpose and insight. 

Spiritual Healing

As a “high-vibration” crystal, cryolite is recommended for meditation to unite the mind, heart, and spirit.

Spiritual practitioners also use cryolite for connecting with higher beings and encouraging natural psychic powers to emerge. 

Cryolite Gemstone Properties

As you know, cryolite is rarely if ever used as a gemstone. Though a few crystals have been faceted, the material has become too rare now. Any material left would only allow for very small faceted gemstones. 

Even synthetic cryolite has the same softness and brittleness as natural material, making it just as difficult to maintain as an accessory. More often, you’ll see cryolite crystals or specimens in collections, though international companies may produce some jewelry with it. 

On the topic of synthetics, how is synthetic cryolite made anyway? 

Synthetics

Manufacturing synthetic granular cryolite usually starts with aluminum hydroxide and hydrofluoric acid. The two react, creating a new acid. Then, sodium chloride is used to change the newly-made acid into a sodium salt. Voila! Synthetic cryolite.

Now, how is real cryolite formed?

Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Cryolite Formation & Sources

Cryolite from Greenland formed inside of a granite pegmatite with many other rare minerals, along with siderite and iron-rich galena. It can also form in alkaline rocks. 

As a salt, cryolite forms when salt water (be it from lakes or oceans) evaporates. You’ll often see minerals like siderite inside or atop cryolite.

Mining Locations

Is cryolite still mined? In small amounts, yes. Although the Greenland deposit was declared “commercially extinct” in the 1980s, there are small amounts elsewhere.

Where is cryolite found, then? 

• Brazil

• Canada

• Namibia

• Russia

• Spain

• USA (Colorado, Virginia)

That means you can still find a cryolite crystal! But how much does cryolite cost?

Cryolite Price & Value

Though rare, cryolite is still pretty affordable. The price of a cryolite crystal for sale is more expensive if it’s from Greenland, with small crystals ranging from $100-$600. 

Cryolite crystals from outside Greenland are generally $12-$50. Tumbled stones are even more budget-friendly, usually between $10-$30. Rough specimens range based on the presence of other minerals, but these typically fetch between $15-$100. 

Cryolite Care and Maintenance

Those aware of fluoride’s danger at high levels may wonder: is cryolite toxic? Somewhat. The U.S. EPA classifies cryolite as a “moderate irritant” but the truly dangerous situation would be working with cryolite powder under heat.

Now, let’s talk gemstone care. Though it won’t completely dissolve in water, it’s slightly soluble. Cryolite will fully dissolve in aluminum chloride or sulfuric acid solutions.

The safest cleaning method is by using a soft brush, warm water, and mild soap. Rinse the stone after, but don’t leave it in water for long. With a soft, dust-free cloth, gently pat the water from the stone. Avoid rubbing or wiping.

Craving A Crystal like Cryolite?

Though most of its significance is in the past, cryolite remains an underrated wonder. Whether you’re looking for a spiritual crystal with potent healing vibrations or a revolutionary artifact that arguably changed the course of modern history, cryolite is the stone for you.

Buy cryolite gemstones today!