Panunzite
A valid IMA mineral species
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About Panunzite
Achille Panunzi collecting at the Procida Island
Procida Island, Metropolitan City of Naples, Campania, Italy
Procida Island, Metropolitan City of Naples, Campania, Italy
Formula:
(K,Na)AlSiO4
Colour:
colourless
Lustre:
Vitreous
Hardness:
5½
Specific Gravity:
2.59
Crystal System:
Hexagonal
Name:
Named by Enrico Franco and Maurizio De Gennaro in 1988 in honor of Achille Panunzi, professor of chemistry, University of Naples. Dr. Panunzi discovered the blocks ejected from Mt. Somma that contained the mineral.
Type Locality:
Isostructural with:
Unique Identifiers
Mindat ID:
3075
Long-form identifier:
mindat:1:1:3075:1
IMA Classification of Panunzite
Classification of Panunzite
9.FA.05
9 : SILICATES (Germanates)
F : Tektosilicates without zeolitic H2O
A : Tektosilicates without additional non-tetrahedral anions
9 : SILICATES (Germanates)
F : Tektosilicates without zeolitic H2O
A : Tektosilicates without additional non-tetrahedral anions
76.2.1.4
76 : TECTOSILICATES Al-Si Framework
2 : Al-Si Framework Feldspathoids and related species
76 : TECTOSILICATES Al-Si Framework
2 : Al-Si Framework Feldspathoids and related species
16.4.2
16 : Silicates Containing Aluminum and other Metals
4 : Aluminosilicates of Na and K
16 : Silicates Containing Aluminum and other Metals
4 : Aluminosilicates of Na and K
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Pnz | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Panunzite
Vitreous
Transparency:
Transparent
Colour:
Colourless
Streak:
White
Hardness:
5½ on Mohs scale
Density:
2.59 g/cm3 (Measured) 2.62 g/cm3 (Calculated)
Optical Data of Panunzite
Type:
Uniaxial (-)
RI values:
nω = 1.540(1) nε = 1.535(1)
Birefringence:
0.005
Max. Birefringence:
δ = 0.005
Based on recorded range of RI values above.
Based on recorded range of RI values above.
Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.
Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.
Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.
Surface Relief:
None to Very Low
Relative to Canada balsam mounting medium (n ≈ 1.537).
Relative to Canada balsam mounting medium (n ≈ 1.537).
This shows the grain boundary and Becke line effect under plane-polarised
light, based on the contrast between this mineral's average refractive
index and the mounting medium. It does not take into account mineral
colouration.
In focus
Interference Figure:
This shows the idealized uniaxial interference figure - the conoscopic
(convergent-light, Bertrand-lens-in) view, for a grain cut with the optic axis
centred and vertical. The coloured rings are isochromatics, computed with the
same physics as the Michel-Lévy bar above; the dark cross is the isogyre.
For a genuinely uniaxial mineral viewed this way, that cross stays perfectly stationary if you rotate the stage - unlike a biaxial mineral, where it splits apart on rotation. That invariance is itself the standard diagnostic test for telling uniaxial and biaxial minerals apart at the microscope.
For a genuinely uniaxial mineral viewed this way, that cross stays perfectly stationary if you rotate the stage - unlike a biaxial mineral, where it splits apart on rotation. That invariance is itself the standard diagnostic test for telling uniaxial and biaxial minerals apart at the microscope.
Pleochroism:
Not Visible
Chemistry of Panunzite
Mindat Formula:
(K,Na)AlSiO4
Element Weights:
Common Impurities:
Fe,Mg,Ca,Sr,Ba,Rb,H2O
Crystallography of Panunzite
Crystal System:
Hexagonal
Class (H-M):
6 - Pyramidal
Space Group:
P63
Cell Parameters:
a = 20.513(8) Å, c = 8.553(3) Å
Ratio:
a:c = 1 : 0.417
Unit Cell V:
3,116.79 ų (Calculated from Unit Cell)
Z:
32
Crystal Structure
Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Show
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
View
CIF File Best | x | y | z | a | b | c
CIF File Best | x | y | z | a | b | c
Rotation
Stop | Start
Stop | Start
Labels
Console Off | On | Grey | Yellow
Console Off | On | Grey | Yellow
Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure
| ID | Species | Reference | Link | Year | Locality | Pressure (GPa) | Temp (K) |
|---|---|---|---|---|---|---|---|
| 0014796 | Panunzite | Merlino S, Franco E, Mattia C A, Pasero M, De Gennaro M (1985) The crystal structure of panunzite (natural tetrakalsilite) Neues Jahrbuch fur Mineralogie, Monatshefte 1985 322-328 | 1985 | Somma-Vesuvius area, Italy | 0 | 293 |
CIF Raw Data - click here to close
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 4.277 Å | (25) |
| 3.929 Å | (70) |
| 3.071 Å | (100) |
| 2.914 Å | (30) |
| 2.558 Å | (40) |
| 2.380 Å | (20) |
| 2.268 Å | (20) |
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 3a: Earth’s earliest Hadean crust | >4.50 |
| 9 : Lava/xenolith minerals (hornfels, sanidinite facies) | |
| Stage 4b: Highly evolved igneous rocks | >3.0 |
| 35 : Ultra-alkali and agpaitic igneous rocks |
Type Occurrence of Panunzite
General Appearance of Type Material:
Hexagonal prisms up to 4 mm in length.
Geological Setting of Type Material:
In cavities in pyroxene-rich ejecta blocks in recent volcanoclastic deposits.
Synonyms of Panunzite
Other Language Names for Panunzite
Common Associates
Related Minerals - Strunz-mindat Grouping
| 9.FA. | Bonaccorsiite | KK2Na3(Al6Si36)O84 |
| 9.FA. | Hexacelsian | BaAl2Si2O8 |
| 9.FA. | Wodegongjieite | KCa3(Al7Si9)O32 |
| 9.FA.05 | Yoshiokaite | (Ca,Na)[Al(Al,Si)O4] |
| 9.FA.05 | Nepheline | Na3K(Al4Si4O16) |
| 9.FA.05 | Trinepheline | NaAlSiO4 |
| 9.FA.05 | Davidsmithite | (Ca,◻)2Na6Al8Si8O32 |
| 9.FA.05 | Kaliophilite | KAlSiO4 |
| 9.FA.05 | Kalsilite | KAlSiO4 |
| 9.FA.05 | 'Carnegieite' | NaAlSiO4 |
| 9.FA.05 | Megakalsilite | KAlSiO4 |
| 9.FA.05 | Trikalsilite | K2NaAl3(SiO4)3 |
| 9.FA.10 | Malinkoite | NaBSiO4 |
| 9.FA.15 | Virgilite | LiAlSi2O6 |
| 9.FA.25 | Lisitsynite | KBSi2O6 |
| 9.FA.30 | Ferrisanidine | K[Fe3+Si3O8] |
| 9.FA.30 | Buddingtonite | (NH4)(AlSi3O8) |
| 9.FA.30 | Rubicline | Rb(AlSi3O8) |
| 9.FA.30 | 'Monalbite' | NaAlSi3O8 |
| 9.FA.30 | Microcline | K(AlSi3O8) |
| 9.FA.30 va | 'Germanate-celsian' | BaAl2Ge2O8 |
| 9.FA.30 | Celsian | Ba(Al2Si2O8) |
| 9.FA.30 | Sanidine | K(AlSi3O8) |
| 9.FA.30 | Orthoclase | K(AlSi3O8) |
| 9.FA.35 | Reedmergnerite | NaBSi3O8 |
| 9.FA.35 | Albite | Na(AlSi3O8) |
| 9.FA.35 | Anorthite | Ca(Al2Si2O8) |
| 9.FA.40 | Paracelsian | Ba(Al2Si2O8) |
| 9.FA.45 | Svyatoslavite | Ca(Al2Si2O8) |
| 9.FA.45 | Kumdykolite | Na(AlSi3O8) |
| 9.FA.50 | Slawsonite | Sr(Al2Si2O8) |
| 9.FA.55 | Lisetite | CaNa2Al4Si4O16 |
| 9.FA.60 | Stronalsite | Na2SrAl4Si4O16 |
| 9.FA.60 | Banalsite | Na2BaAl4Si4O16 |
| 9.FA.65 | Maleevite | BaB2Si2O8 |
| 9.FA.65 | Pekovite | SrB2Si2O8 |
| 9.FA.65 | Danburite | CaB2Si2O8 |
| 9.FA.70 | Liebermannite | KAlSi3O8 |
| 9.FA.70 | Lingunite | NaAlSi3O8 |
| 9.FA.70 | Stöfflerite | CaAl2Si2O8 |
| 9.FA.75 | Pfaffenbergite | KNa3(Al4Si12)O32 |
| 9.FA.75 | Kokchetavite | K(AlSi3O8) |
Radioactivity
Radioactivity:
| Element | % Content | Activity (Bq/kg) | Radiation Type |
|---|---|---|---|
| Uranium (U) | 0.0000% | 0 | α, β, γ |
| Thorium (Th) | 0.0000% | 0 | α, β, γ |
| Potassium (K) | 24.7203% | 7,663 | β, γ |
For comparison:
- Banana: ~15 Bq per fruit
- Granite: 1,000–3,000 Bq/kg
- EU exemption limit: 10,000 Bq/kg
Note: Risk is shown relative to daily recommended maximum exposure to non-background radiation of 1000 µSv/year. Note that natural background radiation averages around 2400 µSv/year so in reality these risks are probably extremely overstated! With infrequent handling and safe storage natural radioactive minerals do not usually pose much risk.
Interactive Simulator:
Note: The mass selector refers to the mass of radioactive mineral present, not the full specimen, also be aware that the matrix may also be radioactive, possibly more radioactive than this mineral!
Activity: –
| Distance | Dose rate | Risk |
|---|---|---|
| 1 cm | ||
| 10 cm | ||
| 1 m |
The external dose rate (D) from a radioactive mineral is estimated by summing the gamma radiation contributions from its Uranium, Thorium, and Potassium content, disregarding daughter-product which may have a significant effect in some cases (eg 'pitchblende'). This involves multiplying the activity (A, in Bq) of each element by its specific gamma ray constant (Γ), which accounts for its unique gamma emissions. The total unshielded dose at 1 cm is then scaled by the square of the distance (r, in cm) and multiplied by a shielding factor (μshield). This calculation provides a 'worst-case' or 'maximum risk' estimate because it assumes the sample is a point source and entirely neglects any self-shielding where radiation is absorbed within the mineral itself, meaning actual doses will typically be lower. The resulting dose rate (D) is expressed in microsieverts per hour (μSv/h).
D = ((AU × ΓU) + (ATh × ΓTh) + (AK × ΓK)) / r2 × μshield
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Panunzite
mindat.org URL:
https://www.mindat.org/min-3075.html
Please feel free to link to this page.
Please feel free to link to this page.
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References for Panunzite
Reference List:
Sahama, Th. G., Smith, J. V. (1957) Tri-kalsilite, a new mineral. American Mineralogist, 42 (3-4) 286
Fleischer, Michael, Chao, George Y., Mandarino, J. A. (1979) New mineral names. American Mineralogist, 64 (5-6) 652-659
Localities for Panunzite
Showing 2 localities.
symbol to view information about a locality.
The Locality List
- This locality has map coordinates listed.
- This locality has estimated coordinates.
ⓘ - Click for references and further information on this occurrence.
? - Indicates mineral may be doubtful at this locality.
- Good crystals or important locality for species.
- World class for species or very significant.
(TL) - Type Locality for a valid mineral species.
(FRL) - First Recorded Locality for everything else (eg varieties).
All localities listed without proper references should be considered as questionable.
Italy (TL) | |
| [Lapis 1994:5 p.13-23 +1 other reference |
| Ciriotti et al. (2004) |
Quick NavTopAbout PanunziteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystal StructureX-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesCommon AssociatesStrunz-MindatRadioactivityOther InformationInternet Links References Localities Locality List
Mount Somma, Metropolitan City of Naples, Campania, Italy