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Leucite Gemstone: Properties, Meanings, Value & More

白榴石寶石：屬性、含義、價值等

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Leucite is a commonly milky, colorless to gray gemstone that’s rare in gem-quality form — only Italy is known to produce gem-quality leucite crystals.

Even the leucite-bearing rock leucitite is rare, with many nations not containing a single one.

The leucite mineral is important industrially, but it’s important to note that it’s not the same as the industrial material lucite. “Lucite” is the trademarked name for a synthetic acrylic plastic resin mostly used in windows and interior design.

Come along to learn all about leucite’s mineral and gemstone traits, along with its meanings, prices, history, and more!

Image credit: Parent Géry | Creative Commons Attribution-Share Alike 3.0 Unported license

About Leucite Stone

Leucite is a semi-precious gemstone that’s also called:

• Amphigene

• Grenatite

• Leukolith

• Oeil de perdrix (French for “partridge eyes”)

The last name listed is a specific rosé wine from Switzerland, possibly chosen to describe uncommonly pinkish leucites.

Another common nickname (and misnomer) for leucite is “white garnet,” since leucite looks isometric and is often milky white. It even shares etymology with the colorless grossular garnet variety “leuco garnet.” However, they’re completely different minerals.

Astrologically, leucite is considered beneficial for those born under Cancer, Pisces, and Leo.

Industrially, what is leucite used for?

Leucite Uses

The leucite mineral has many industrial uses, and scientists have created synthetic versions for research. Leucite is used as fertilizer and for sourcing commercial alum (potassium aluminum sulfate or ammonium aluminum sulfate often used in medical astringents).

In dentistry, leucite is a significant component of ceramics — used for restorations like bridges, crowns, and veneers.

Dentists use leucite-reinforced ceramic because it increases the material’s coefficient of thermal expansion (meaning it expands more when it’s heated, so it won’t crack as easily). It’s also translucent with high flexural strength (bends further instead of breaking) and compressive strength (resists breaking under pressure).

Leucite is also used in dental porcelains, another type of ceramic.

Pictured above: Pseudoleucite (Pseudomorph of kaolinite after leucite)| Image credit: Eurico Zimbres

Leucite Specifications & Characteristics

As a potassium aluminosilicate, leucite’s formula is KAISi2O6. Common impurities in leucite are titanium, iron, magnesium, calcium, barium, sodium, rubidium, caesium, and water.

Petrologists classify leucite in the feldspathoid group of tectosilicate minerals similar to feldspars but with different structures and lower silica content. However, it’s also often included in the zeolite mineral group because of its topological similarities to zeolites like analcime.

What is the crystal form of leucite? The most common leucite habit is trapezohedral crystals, but it can also be granular or form euhedral, pseudo-cubic crystals. Twinning is common but hard to see because of leucite’s low birefringence.

The mineral may pseudomorph (different chemistry, same shape) from exposure into pseudoleucite — a mixture of nepheline and orthoclase feldspar — and further alter into kaolinite with more exposure.

Leucite properties listed:

• Mohs hardness: 5.5-6

• Color: Colorless, white, ash-gray, smoky gray, yellow, reddish

• Crystal structure: Tetragonal, pseudo-cubic/pseudo-isometric; Isometric/cubic above 625°C (1157°F), tetragonal below that temperature

• Luster: Vitreous or subvitreous when fresh, alters to waxy/greasy, then dull

• Transparency: Transparent to translucent; May become opaque over time

• Refractive index: 1.504-1.509

• Density: 2.45-2.50

• Cleavage: Poor/indistinct; Very poor on {110}

• Fracture: Conchoidal

• Streak: White

• Luminescence: Sometimes fluorescence - medium-bright orange to violet in LW-UV; Sometimes X-ray colors - bluish

• Pleochroism: None

• Birefringence: 0.000-0.001 (very low)

• Dispersion: 0.008-0.010 (weak); Can appear stronger due to twinning

How Do You Identify Leucite?

Two minerals that may be mixed up with leucite are analcime and garnet.

Garnet is easier to distinguish, as it has greater hardness, higher refractive indices, higher density, and brighter colors than leucite. Analcime is trickier, but it’s slightly less dense with a slightly lower refractive index and typically a more reflective luster.

Generally, you can identify leucite by its optical properties.

The stone is technically isotropic, but it's tetragonal crystal axes of different lengths make some specimens doubly-refractive (birefringent). This weak birefringence means you’ll see gray interference colors.

Though leucite crystallizes isometrically at high temperatures, it will recrystallize tetragonally when cooled but still look isometric externally. This alteration often results in twinning and striation.

The cross section of leucite crystals is usually octagonal. You can also look for complex twinning in many directions.

Pictured above: Thin section of leucite | Image credit: Petr Hykš, Flickr; Creative Commons Attribution-Share Alike 2.0 Unported license

Leucite Meaning & History

Leucite crystals symbolize unity, purification, and inspiration. It’s commonly associated with feminine power, openness, and spiritual awareness.

As an earth energy stone, leucite possesses the energies of balance, stability, and the nourishment of feeling at home.

But what is the origin of leucite?

History

The name “leucite” derives from the Greek term leukos, meaning “(matte) white,” after its most common color. This name, along with the mineral’s first official description, came from German geoscientist Abraham Gottlob Werner in 1791.

However, ancient mineralogical references to a “white garnet” may have actually been referring to leucite.

French mineralogist René Just Haüy first used the synonym “amphigene” (or “amphigène”) in 1803. Older French mineralogical literature may use this term, but the International Mineralogical Association (IMA) only officially recognizes “leucite.”

The type locality of leucite is Mount Vesuvius in Italy. Much of the research on leucite from this locality came from Italian mineralogist Arcangelo Scacchi, notably from 1872 to 1882.

In 1821, British scientist Sir David Brewster first observed that leucite crystals weren’t isotropic and thus only pseudo-cubic. German mineralogist Gerhard vom Rath concluded that leucite was tetragonal in 1873.

The first leucite in North America was discovered in the subsequently named Leucite Hills of Wyoming in 1871. Leucites were discovered in Australia in 1887.

Back to the metaphysical, what are the healing properties of leucite?

Leucite Healing Properties

As a colorless healing stone, leucite joins other colorless and white gemstones in offering clarity, cleansing, and spiritual ascension. White gems like leucite are also great crown chakra stones.

Physical Healing

Physically, leucite crystals are said to treat or help with:

• Insomnia

• Headaches

• Immune deficiency

• Recovery from illness or injury

Emotional Healing

Crystal healers recommend leucite for strengthening relationships and self-confidence. It may promote wise decision-making by grounding you, making you more aware of your deepest needs, and dispelling stress clouding your judgment.

Pictured above: Leucite crystals on quartz | Image credit: Parent Géry | Creative Commons Attribution-Share Alike 3.0 Unported license

Leucite Gemstone Properties

Leucite value depends on gemstone properties like color, cut, clarity, transparency, and carat weight.

Color

Leucite is most often colorless, white, or gray. But impurities can make it yellow or reddish. Freshly cut crystals are transparent and glassy, but can become duller over time.

Fascinatingly, leucites can display unusually high fire, despite their weak dispersion and low birefringence. Gemologists believe twinning and striation allow some leucites to have an opal-like play-of-color, regardless of their cut.

Cut

Because gem-quality leucite crystals are rare, so are faceted gems, making them highly valuable and sought-after (especially by collectors).

Attractive specimens may be sold uncut, shaped into cabochons, or made into leucite stone beads.

Clarity & Transparency

The majority of leucite crystals are cloudy, so greater transparency means greater value.

Most leucite crystals have more inclusions the larger they get. Common inclusions are concentric zones of crystals like:

• Apatite

• Augite

• Magnesite

• Olivine

• Spinel

• Natural glass

Leucite gems can also have stained fractures.

Carat Weight & Size

Leucite crystals don’t get very large, only up to about 12 cm. The largest faceted gems are only around 3 carats. Larger crystals tend to have more inclusions.

Pictured above: Microphotograph under an optical microscope of skeletal leucite crystals coming from the Colli Albani volcano in Italy | Image credit: SNSF Scientific Image Competition, Flickr; Creative Commons Attribution-Share Alike 2.0 Unported license

Leucite Formation & Sources

Leucite is only found in igneous rocks, specifically potassium-rich, silica-poor ones. It’s common in young lava rocks like lamproite. It can crystallize from potassium-rich, silica-poor magma or via paragenesis with high-alumina and high-alkali minerals.

When leucite first forms at high temperatures, it crystallizes with a cubic structure. When it cools to 700-600°C, it becomes tetragonal.

Leucite is found with natrolite, nepheline, olivine, biotite, augite, and analcime.

Mining Locations

Where does leucite come from? The only currently known source of gem-quality (transparent & facetable) leucite crystals is Italy.

The mineral is also found in:

• Australia

• Brazil

• Canada

• Democratic Republic of Congo

• France

• Germany

• Tanzania

• Turkey

• Uganda

• USA (Arkansas, Montana, New Jersey, Wyoming)

Onto leucite’s cost!

Pictured above: Garnet-shaped leucite crystal now replaced by orthoclase | Image credit: Rob Lavinsky, iRocks.com – CC-BY-SA-3.0

Leucite Price & Value

Faceted leucite gemstones range in price from around $35 to $450 per carat or around $25 to $220 each. Remember: most faceted leucites are under 1 carat.

Rough leucite crystals vary in price by their size and quality. Most leucite crystals cost about $20 to $30 each, but they can be as low as $5 or as high as $800 for enormous specimens.

Jewelry like strands of leucite beads is usually inexpensive, as low as $15.

Leucite Care and Maintenance

Lastly, we’ll discuss gemstone care. With mid-range hardness and brittle tenacity, leucite is fairly easy to take care of, but jewelry should have protective settings.

You can clean leucite with a soft brush, mild soap, and warm water.

Store leucite separately from other gemstones to avoid scratches.

In Love with Leucite Already?

Leucite may look ordinary, but from its many transformations to its unusual fire to its healing powers, there’s plenty of magic hiding inside. This intriguing crystal belongs in any rare gem collection!

Buy leucite and other lavish gemstones today!