Hauyne

(Na,Ca)4-8(Al6Si6O24)(SO4,S)1-2; sodium calcium aluminosilicate with sulfate/sulfide · Mohs 5.5 · Cubic · Third Eye Chakra

The stone of hauyne: meaning, mineralogy, and somatic practice.

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This page documents traditional and cultural uses of hauyne alongside emerging research on tactile grounding objects. Crystalis does not claim that hauyne treats, cures, or prevents any medical condition. For mental health concerns, consult a qualified professional.

Crystalis Editorial · 40+ Years · Herndon, VA · 8 peer-reviewed sources

Origins: Germany (Eifel), Italy, Morocco

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Materia Medica

Hauyne

The Rare Blue of Expression

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Protocol

The Volcanic Sapphire

A rare feldspathoid born in volcanic fire, hauyne teaches that brilliance can emerge from the most violent origins.

3 min

1
Hold the hauyne specimen at eye level. Notice its vitreous-to-greasy luster — that brilliance is a sodium-calcium aluminosilicate born inside volcanic vents. Let your eyes receive the blue without naming it. Settle your weight evenly between both feet.
2
Lower the stone to your throat. Hauyne belongs to the sodalite mineral group — it carries sulfur locked inside a cubic crystal cage. Breathe in for four counts through the nose. Exhale for six through the mouth, as though releasing pressure from a sealed chamber.
3
Close your eyes. Ask: where in my body has creative expression gone dormant — not because it was never there, but because the heat that formed it also exhausted it? Sit with whatever surfaces. Do not interpret.
4
Open your eyes. Turn the hauyne slowly in your fingers, catching light on different faces. The same stone appears different at every angle. Notice one thing you have made, said, or offered that you forgot was beautiful. Set the stone down when the recognition lands.

tap to flip for protocol

There are moments when the psyche needs a jolt, not a lullaby. The system has gone dim, and what is required is not more patience but a denser shot of color, something vivid enough to wake the whole field at once.

Hauyne does that with startling efficiency. A small feldspathoid with volcanic origin, it carries an ultramarine blue so concentrated it can look almost artificial against the rock that holds it. The scale stays modest. The signal does not.

Hauyne feels like ignition rather than comfort. It proves intensity is not proportional to size. A small source can still change the atmosphere.

What Your Body Knows

Nervous system states

At the throat and upper chest, hauyne corresponds to compressed intensity. It is useful for states where expression is not absent but condensed, waiting for a clean release point.

In sympathetic activation, that can appear as speech held too tightly, bright thoughts with no outlet, or a body carrying more charge than its size suggests. Hauyne offers an image of small volume with vivid signal, formed in chemically unusual volcanic conditions. That makes it particularly apt for people who underestimate the force inside them because the container looks modest.

In lower-energy states, the same mineral can supply a visual spark without the sprawling field of larger blue stones. It works most clearly with inhibited declaration, compacted self-expression, and the need for a bright but controlled outlet. The message is that intensity does not require mass to be real. In practice, hauyne's cubic sodalite-group structure with Mohs 5.5 and specific gravity around 2.45 produces a small, vivid specimen with more visual signal than its mass would suggest. The lazurite-relative blue is direct and saturated, giving the eyes a concentrated color experience. Held at the throat notch or placed at the collarbone, hauyne provides a point-source of chromatic intensity that can help compressed expression find its exit point. It is the stone for the person who has been told they are too much and suspects, correctly, that they are only too small a container.

sympathetic

Dorsal vagal collapse (creative shutdown):

Hauyne's brilliant, almost electric blue has a quality distinct from lazurite's deep, contemplative blue. Hauyne's blue is bright, alert, present

dorsal vagal

Overwhelm states (dorsal vagal tendencies toward shutdown under information overload):

Hauyne's vivid blue from the S3- radical; a single, precise chromophore producing a clear signal; offers a somatic metaphor for finding the one clear note in cacophony. Useful for those who freeze when facing too many choices. - Throat/voice activation: Blue stones have traditional associations with communication. Hauyne's connection to the framework silicate structure (where every atom has a defined place in the cage) maps to structured expression; saying what you mean, precisely. - Transition states: Hauyne forms in volcanic environments during eruption; the moment of transformation from deep earth to surface. Useful during life transitions where the old framework is dissolving and new structures have not yet solidified.

dorsal vagal

I have nothing left

Mixed state: ventral + sympathetic (enthusiastic engagement):

ventral vagal

Sympathetic depletion with social mask (performing fine while exhausted):

When already socially regulated but creatively energized, hauyne amplifies the bright, expressive quality of this optimal state. Its rarity and brilliance mirror the preciousness of moments when we are both safe and on fire

ventral vagal

pumice shell

Dorsal vagal with grief (the deep quiet after loss): The extreme rarity of gem-quality hauyne (most specimens are too small, too included, or too fractured for faceting) gives it an association with preciousness-in-loss. What survives volcanic destruction intact is profoundly rare. For a nervous system moving through grief; where something irreplaceable has been lost; hauyne validates the rarity of what was and honors it without attempting to replace it. State shift: grief-frozen dorsal toward honoring loss as evidence of value.

Nervous system mapping based on polyvagal theory (Porges, S.W. The Polyvagal Theory. Norton, 2011).

The Earth Made This

Formation: How Hauyne Becomes Hauyne

Haüyne (also hauyne or hauynite) is a sodalite-group feldspathoid that forms in silica-undersaturated igneous rocks, particularly phonolites and some nepheline syenites. Named after French crystallographer René Just Haüy, the mineral crystallizes in the cubic system as dodecahedral or octahedral crystals. The vivid blue color (which can rival lazurite) comes from the sulfate and sulfide anions enclosed in the sodalite cage structure.

Haüyne forms only in alkaline magmatic environments where silica activity is too low for feldspar to form, and calcium and sulfur are both available. The Eifel volcanic region of Germany produces the finest gem-quality haüyne crystals, typically small but exceptionally vivid blue. Haüyne is one of the four minerals that compose lapis lazuli.

Material facts

What the stone is made of

Mineralogy: Sodalite-group feldspathoid, tectosilicate class. Chemical formula: (Na,Ca)₄₋₈(Al₆Si₆O₂₄)(SO₄,S)₁₋₂. Crystal system: cubic. Mohs hardness: 5.5-6. Specific gravity: 2.44-2.50. Color: vivid blue, from S₃⁻ trisulfide radical anion trapped within the sodalite cage structure (the same chromophore responsible for the blue in lazurite and ultramarine pigment). Luster: vitreous to greasy. Habit: dodecahedral or rounded grains. Isometric with sodalite, nosean, and lazurite. Distinguished from lazurite by higher calcium content and lower sulfide.

Deeper geology

In silica-poor alkaline volcanic systems, where feldspar cannot easily satisfy the chemistry, feldspathoids enter the scene. Hauyne is one of them, a member of the sodalite group with complex sodium, calcium, aluminum, silicon, sulfate, and sulfide chemistry. It crystallizes in the cubic system, often as dodecahedral grains or small crystals, and its intense blue belongs to sulfur species trapped in the aluminosilicate cage structure. The same family resemblance links it conceptually to lazurite and the ultramarine blue long prized in pigment history.

Formation requires silica-undersaturated magmas such as phonolites and nepheline-bearing alkaline rocks. In those settings, the melt chemistry leaves room for feldspathoids rather than ordinary feldspars. Sulfur-bearing volatiles also remain available, and cage-like tectosilicate structures can trap sulfate and sulfide anions during crystallization. Hauyne therefore records an unusual chemical regime, one far from the granitic norm. Hardness sits around 5.5 to 6, specific gravity around 2.45, and the crystals are typically small, making color the first thing the eye notices.

That color is scientifically specific. Blue in hauyne is linked to sulfur radical species, not to copper or cobalt. The mineral is therefore a lesson in how nonmetal chromophores can dominate visual identity. It also reminds mineralogists that igneous rarity often comes from the chemistry of what is absent. Here, low silica is the enabling condition.

The somatic turn arrives as ignition in compact form. Hauyne is a small-body stone with disproportionate intensity, forged in magmas chemically unlike the ordinary crustal template. For the body, it reads as vivid signal emerging from uncommon conditions rather than from size or mass.

Mineralogy

Mineral specs

Chemical Formula

(Na,Ca)4-8(Al6Si6O24)(SO4,S)1-2; sodium calcium aluminosilicate with sulfate/sulfide

Crystal System

Cubic

Mohs Hardness

5.5

Specific Gravity

2.44-2.50

Luster

Vitreous to greasy; gem-quality specimens display remarkable brilliance for a feldspathoid

Color

Blue

Crystal system diagram represents the general cubic classification. Diagram created by Crystalis for educational reference.

Traditional Knowledge

Lore and culture around Hauyne

Science grounds the page. Tradition, lore, and remembered use make it readable as lived knowledge.

German Eifel volcanic tradition: The Laacher See caldera region has been a mineral-collecting locality since at least the Roman period. Local tradition holds that the brilliant blue crystals found in pumice were "frozen lightning"; pieces of the sky trapped in stone during the eruption. The mineral was formally described in 1807 by Bruun-Neergaard and named in honor of Rene Just Hauy (1743-1822), the French crystallographer considered the father of modern crystal structure theory. The Eifel remains the only significant source of gem-quality hauyne in the world (Friis, 2011).

Italian volcanic mineralogy (Vesuvius/Latium): Hauyne has been recognized in the volcanic products of the Somma-Vesuvius complex and the Latium volcanic provinces since the early 19th century. Italian specimen hauyne was crucial to the original scientific understanding of the sodalite mineral group. The species was first formally defined from Italian specimens by mineralogist Carlo Giuseppe Gismondi in 1803, predating the current name (Della Ventura et al., 2019). In Naples, volcanic minerals including hauyne were incorporated into both scientific collections and folk healing traditions associated with Vesuvius.

Contemporary gem collecting (21st century): Hauyne has become one of the most sought-after collector gemstones of the modern era. A well-cut, eye-clean hauyne over 1 carat from the Eifel can command prices exceeding $3,000-5,000 per carat; comparable to fine sapphire. Its extreme rarity (far rarer than diamond or sapphire), combined with its remarkable brilliance for a non-traditional gemstone, has made it a prestige mineral among serious gem collectors. Major auction houses have featured exceptional hauyne specimens as individual lots.

Medieval German healing traditions: In the Rhineland, where hauyne-bearing pumice was used as building stone (the city of Andernach was built partly of Laacher See pumice), folk healers recognized the small blue crystals as having "sky medicine" properties. The association of blue volcanic crystals with celestial healing mirrors similar traditions in Italy around Vesuvius minerals. These traditions predate formal mineralogical identification of hauyne as a distinct species.

Unknown

1807

Rene Just Hauy publishes foundational work on crystal symmetry; hauyne later named in his honor - 1822: First formal mineral description of hauyne from Eifel volcanic specimens - 19th century: Primarily a mineralogical curiosity due to rarity and small crystal size - 20th-21st century: Growing interest as a collector's gemstone; faceted hauyne has become one of the rarest blue gemstones on the market - 2010s-present: Gem hauyne from Eifel and Morocco commands premium prices; stones over 1 carat are exceptional rarities

Unknown

German Eifel volcanic tradition

The Laacher See caldera region has been a mineral-collecting locality since at least the Roman period. Local tradition holds that the brilliant blue crystals found in pumice were "frozen lightning" -- pieces of the sky trapped in stone during the eruption. The mineral was formally described in 1807 by Bruun-Neergaard and named in honor of Rene Just Hauy (1743--1822), the French crystallographer considered the father of modern crystal structure theory. The Eifel remains the only significant source of gem-quality hauyne in the world (Friis, 2011). 2. Italian volcanic mineralogy (Vesuvius/Latium): Hauyne has been recognized in the volcanic products of the Somma-Vesuvius complex and the Latium volcanic provinces since the early 19th century. Italian specimen hauyne was crucial to the original

Sacred Match Notes

When this stone becomes the right door

Sacred Match prescribes Hauyne when you report:

Throat charge held too tightly

Need compact intensity

Small body, strong signal

Bright thought needing outlet

Upper chest wants declaration

Expression compressed not absent

Sacred Match prescribes through physiological diagnosis, not preference. It queries the nervous system: current sensation, protective mechanism, and the biological need masked by both. When that triangulation reveals throat charge held too tightly, hauyne enters the protocol.

Throat charge held too tightly -> state identified in the body -> seeking regulation through this stone's specific structure

Need compact intensity -> protective pattern active -> seeking correction

Small body, strong signal -> current nervous system demand -> seeking support

Bright thought needing outlet -> adaptation seeking revision -> seeking revision

Upper chest wants declaration -> old strategy still running -> seeking a more current pattern

The prescription is specific because the state is specific. Sacred Match does not sort by favorite color or trend language. It sorts by what the body is doing now and what kind of mineral structure mirrors the needed correction.

3-Minute Reset

The Volcanic Sapphire

A rare feldspathoid born in volcanic fire, hauyne teaches that brilliance can emerge from the most violent origins.

3 min protocol

1
Hold the hauyne specimen at eye level. Notice its vitreous-to-greasy luster — that brilliance is a sodium-calcium aluminosilicate born inside volcanic vents. Let your eyes receive the blue without naming it. Settle your weight evenly between both feet.
40 sec
2
Lower the stone to your throat. Hauyne belongs to the sodalite mineral group — it carries sulfur locked inside a cubic crystal cage. Breathe in for four counts through the nose. Exhale for six through the mouth, as though releasing pressure from a sealed chamber.
40 sec
3
Close your eyes. Ask: where in my body has creative expression gone dormant — not because it was never there, but because the heat that formed it also exhausted it? Sit with whatever surfaces. Do not interpret.
50 sec
4
Open your eyes. Turn the hauyne slowly in your fingers, catching light on different faces. The same stone appears different at every angle. Notice one thing you have made, said, or offered that you forgot was beautiful. Set the stone down when the recognition lands.
50 sec

The #1 Question

Can Hauyne go in water?

Water Safety NO -- Do not submerge. Hauyne is a feldspathoid with moderate hardness (5.5--6) and a framework structure containing sulfate groups that can be slowly leached by water, particularly acidic solutions. Gem-quality specimens are extremely fragile and valuable -- any water damage could be catastrophic financially and energetically. Brief rinsing under gentle running water for cleaning is marginally acceptable but not recommended for gem-quality pieces. Never soak. Never use in gem elixirs. Use dry cleaning methods (soft brush) or energetic cleansing (smoke, sound, moonlight).

Mineral Distinction

What sets Hauyne apart

Hauyne is a deep blue feldspathoid mineral in the sodalite group, and the market confusion involves lazurite, sodalite, and occasionally blue glass or synthetic material. At Mohs 5. 5 to 6 with specific gravity 2.

44 to 2. 50, hauyne is lighter than most blue gem materials and forms isometric crystals, typically dodecahedral, rather than the massive habit more common in sodalite and lazurite. The blue color comes from sulfur related S3 minus radical color centers, the same chromophore as lazurite.

Genuine hauyne is relatively rare as faceted gems and typically shows a vivid electric blue that can rival fine sapphire at a fraction of the hardness. Sodalite is usually more opaque and massive. Lazurite is the blue component of lapis lazuli, not normally seen as individual crystals.

If a small vivid blue gem is offered as hauyne without a gem lab report, confirm the isometric crystal system and specific gravity before paying collector prices.

Care and Maintenance

How to care for Hauyne

- Water: Generally safe for brief contact; hauyne is not water-soluble. However, prolonged soaking is not recommended as the sulfate groups within the structure may be susceptible to slow leaching in acidic conditions. - Hardness: 5.

5-6 Mohs. Moderately durable. Conchoidal fracture and imperfect cleavage mean some fragility.

- Sun: Prolonged UV exposure not well studied for color stability; exercise caution with valuable specimens. - Heat: Avoid extreme heat. As demonstrated in laboratory studies, heating above 750 degrees C in air alters sulfur speciation and color.

- Skin: Safe for direct contact. - Rarity note: Extremely rare mineral. Most specimens should be treated as irreplaceable.

Handle with care.

Crystal companions

What pairs well with Hauyne

Lapis Lazuli

Shared sulfur-blue lineage. Lapis carries aggregate historical depth, while hauyne expresses similar chromophore chemistry in a more discrete mineral form. Together they suit work around voice, intensity, and historical continuity. Place lapis at the throat and hauyne on a writing desk.

Carnelian

Blue ignition with orange drive. Carnelian warms and mobilizes what hauyne electrifies. Good for speaking with confidence rather than restraint. Keep carnelian in the lower pocket and hauyne higher, near the collar or notebook.

Black Tourmaline

Bright signal, strong perimeter. Hauyne can feel too sharp on its own, especially in overstimulating environments. Black tourmaline gives it grounding and containment. Put tourmaline at the base of the room and hauyne at eye level.

Iolite

Color intensity with directional depth. Iolite shifts by angle, hauyne strikes almost immediately. This pair works when someone needs both subtle perspective and unmistakable declaration. Place iolite in the left palm and hauyne in the right during reflective practice.

Clear Quartz

Reference and amplification. When a pairing needs one neutral witness, clear quartz does that job. It does not replace the main relationship. It clarifies it, making the dominant stone easier to read and easier to place with intention. Keep clear quartz beside the central specimen on a desk, shelf, or nightstand so the arrangement stays visually legible.

In Practice

How Hauyne is used

Hauyne's somatic signature aligns with clarity within complexity. the capacity to find signal within noise. As a mineral that forms only under specific, narrow geochemical conditions (silica-undersaturated, sulfate-bearing, alkaline), it resonates with:

- Overwhelm states (dorsal vagal tendencies toward shutdown under information overload): Hauyne's vivid blue from the S3- radical. a single, precise chromophore producing a clear signal. offers a somatic metaphor for finding the one clear note in cacophony. Useful for those who freeze when facing too many choices. - Throat/voice activation: Blue stones have traditional associations with communication. Hauyne's connection to the framework silicate structure (where every atom has a defined place in the cage) maps to structured expression. saying what you mean, precisely. - Transition states: Hauyne forms in volcanic environments during eruption. the moment of transformation from deep earth to surface. Useful during life transitions where the old framework is dissolving and new structures have not yet solidified.

- When needing clarity before an important communication - During decision-making where the signal is buried in noise - When transitioning between life phases or identities

- Not during states of deep grief (too activating; the blue wavelength can feel demanding) - Not when already in a hyper-verbal, over-communicative state (hauyne amplifies precision, not volume)

Verification

Authenticity

Hauyne: vivid blue sodalite-group mineral from volcanic rocks. Mohs 5. 5-6.

Specific gravity 2. 44-2. 50.

Vitreous to greasy luster. Cubic system. Gem-quality hauyne is extremely rare and expensive.

Distinguished from lazurite (lower SG, different host rock) and sodalite (slightly different blue, often paler). If offered cheaply as gem-quality, verify.

Temperature

Natural Hauyne should usually feel cooler than plastic or resin on first touch and warm more slowly in the hand.

Scratch logic

Use 5.5 on the Mohs scale as the check, not internet myths. A real specimen should behave in line with the hardness listed above.

Surface and luster

Look for a vitreous to greasy; gem-quality specimens display remarkable brilliance for a feldspathoid surface quality rather than a painted or plastic shine.

Weight and density

The listed specific gravity is 2.44-2.50. If a specimen feels unusually light for its size, it may deserve a second look.

Geographic Origins

Where Hauyne forms in the world

Eifel volcanic district, Germany . Type locality (Laacher See area); gem-quality blue crystals in phonolite Mount Vulture (Melfi), Italy . Well-studied phenocrysts in hauynophyre; blue, white, grey, and black varieties Alban Hills (Latium), Italy . Volcanic rocks with sodalite-group minerals Morocco . Gem-quality transparent blue crystals Mogok, Myanmar . Rare gem specimens Palabora, South Africa . In alkaline intrusive complex Cripple Creek, Colorado, USA . In phonolite

Hauyne is a feldspathoid mineral that forms exclusively in silica-undersaturated alkaline igneous rocks . it is thermodynamically incompatible with free quartz. Its occurrence is restricted to phonolites, nephelinites, leucitites, and related volcanic and plutonic lithologies where the magma's alkali content exceeds that required to form feldspar, and silica activity is too low for feldspar alone to crystallize. The mineral characteristically occurs as phenocrysts in phonolitic lavas, where it crystallizes at relatively high temperatures (approximately 800-1000 degrees C) from sulfate-bearing, alkali-rich melts. The sodalite-group structure consists of a framework of alternating SiO4 and AlO4 tetrahedra forming a cage-like arrangement (beta-cages or sodalite cages) that enclose anion groups . in hauyne's case, sulfate (SO4)2- groups and associated sodium/calcium cations (Caggiani et al., 2022, doi:10.1002/jrs.6310; Della Ventura et al., 2019, doi:10.1002/jrs.5665). Hauyne's host rocks . phonolites and related volcanics . are associated with continental rift systems, oceanic island volcanism, and other tectonic settings where mantle-derived, alkaline magmatism occurs. The Eifel volcanic field in Germany, Mount Vulture in southern Italy, and the Laacher See volcanic complex are classic localities. These volcanic systems tap deep mantle sources enriched in incompatible elements and volatiles, producing the specific melt compositions necessary for feldspathoid crystallization (Della Ventura et al., 2019, doi:10.1002/jrs.5665).

FAQ

Frequently asked

What is Hauyne?

Chemical formula: (Na,Ca)4-8(Al6Si6O24)(SO4,S)1-2 -- sodium calcium aluminosilicate with sulfate/sulfide. Mohs hardness: 5.5--6. Crystal system: Cubic (isometric), space group P-43n.

What is the Mohs hardness of Hauyne?

Hauyne has a Mohs hardness of 5.5-6.

Can Hauyne go in water?

Can Hauyne go in the sun?

Prolonged UV exposure not well studied for color stability; exercise caution with valuable specimens.

What crystal system is Hauyne?

Hauyne crystallizes in the Cubic (isometric), space group P-43n.

What is the chemical formula of Hauyne?

The chemical formula of Hauyne is (Na,Ca)4-8(Al6Si6O24)(SO4,S)1-2 -- sodium calcium aluminosilicate with sulfate/sulfide.

Is Hauyne toxic?

Gem-quality hauyne is notoriously fragile. The crystals often contain internal inclusions and fracture planes from volcanic stress. Handle with extreme care. Do not subject to thermal shock, ultrasonic cleaning, or steam cleaning. Store individually wrapped in soft cloth.

Where is Hauyne found?

- Eifel volcanic district, Germany -- Type locality (Laacher See area); gem-quality blue crystals in phonolite - Mount Vulture (Melfi), Italy -- Well-studied phenocrysts in hauynophyre; blue, white, grey, and black varieties - Alban Hills (Latium), Italy -- Volcanic rocks with sodalite-group minerals - Morocco -- Gem-quality transparent blue crystals - Mogok, Myanmar -- Rare gem specimens - Palabora, South Africa -- In alkaline intrusive complex - Cripple Creek, Colorado, USA -- In phonolite ---

References

Sources and citations

Dentith, Michael, Enkin, Randolph J., Morris, William, Adams, Cameron, Bourne, Barry. (2019). Petrophysics and mineral exploration: a workflow for data analysis and a new interpretation framework. Geophysical Prospecting. [SCI]
DOI: 10.1111/1365-2478.12882
De Benedetto, Giuseppe E., Fico, Daniela, Margapoti, Eleonora, Pennetta, Antonio, Cassiano, Antonio et al. (2013). The study of the mural painting in the 12th century monastery of Santa Maria delle Cerrate (Puglia‐Italy): characterization of materials and techniques used. Journal of Raman Spectroscopy. [SCI]
DOI: 10.1002/jrs.4298
Mangone, A., Caggiani, M.C., Forleo, T., Giannossa, L.C., Acquafredda, P. (2023). A Possible Natural and Inexpensive Substitute for Lapis Lazuli in the Frederick II Era: The Finding of Haüyne in Blue Lead-Tin Glazed Pottery from Melfi Castle (Italy). [LORE]
Della Ventura, Giancarlo, Capitelli, Francesco, Sbroscia, Marco, Sodo, Armida. (2019). A Raman study of chalcogen species in sodalite‐group minerals from the volcanic rocks of Latium (Italy). Journal of Raman Spectroscopy. [SCI]
DOI: 10.1002/jrs.5665
Caggiani, Maria Cristina, Acquafredda, Pasquale, Colomban, Philippe, Mangone, Annarosa. (2014). The source of blue colour of archaeological glass and glazes: the Raman spectroscopy/SEM‐EDS answers. Journal of Raman Spectroscopy. [SCI]
DOI: 10.1002/jrs.4492
Chaouche, Mohend, Gao, Xiao Xiao, Cyr, Martin, Cotte, Marine, Frouin, Laurent. (2017). On the origin of the blue/green color of blast‐furnace slag‐based materials: Sulfur K‐edge <scp>XANES</scp> investigation. Journal of the American Ceramic Society. [SCI]
DOI: 10.1111/jace.14670
Caggiani, Maria Cristina, Mangone, Annarosa, Acquafredda, Pasquale. (2022). Blue coloured haüyne from Mt. Vulture (Italy) volcanic rocks: SEM‐EDS and Raman investigation of natural and heated crystals. Journal of Raman Spectroscopy. [SCI]
DOI: 10.1002/jrs.6310
Colomban, Philippe, Tournié, Aurélie, Caggiani, Maria Cristina, Paris, Céline. (2012). Pigments and enamelling/gilding technology of Mamluk mosque lamps and bottle. Journal of Raman Spectroscopy. [SCI]
DOI: 10.1002/jrs.4101

Closing Notes

Hauyne

A sodalite-group feldspathoid from silica-undersaturated igneous rocks. Named after a French crystallographer. Blue from sulfur radical anions, the same color mechanism as lapis lazuli.

The science documents how lazurite chemistry repeats in a different mineral framework. The practice asks what it means when two different structures produce the same blue from the same atomic source.

Field Notes