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Fantappièite

A valid IMA mineral species
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03797730017272051422440.jpg
Fantappièite

Fosso La Nova, Farnese, Viterbo Province, Lazio, Italy
05609640017272039215017.jpg
Fantappièite

Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
03538250017272050308807.jpg
Fantappièite

Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
09960810017272471588442.jpg
Fantappièite

Fosso La Nova, Farnese, Viterbo Province, Lazio, Italy
04555420017866506003951.jpg
Fantappièite

Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
03538250017272050308807.jpg
Fantappièite

Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
03797730017272051422440.jpg
Fantappièite

Fosso La Nova, Farnese, Viterbo Province, Lazio, Italy
05609640017272039215017.jpg
Fantappièite

Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
Hide all sections | Show all sections

About FantappièiteHide

Formula:
[Na82.5Ca33K16.5](Si99Al99O396)(SO4)33 · 4H2O
Colour:
colorless
Lustre:
Vitreous
Hardness:
6
Specific Gravity:
2.471 (Calculated)
Crystal System:
Trigonal
Name:
for Acasto Liberto Fantappiè (Pontassieve, 1862–Viterbo, 1933), a distinguished geologist and naturalist who dedicated part of his scientific activity to the mineralogy and petrology of the volcanic rocks of the Roman Comagmatic Region in the Sabatini area where the mineral has been found.
Cancrinite Group.


Name EncodingHide

ASCII-7:
Fantappieite

Unique IdentifiersHide

Mindat ID:
35970
Long-form identifier:
mindat:1:1:35970:8

IMA Classification of FantappièiteHide

IMA status:
Approved
IMA Formula:
[Na82.5Ca33K16.5]Σ=132(Si99Al99O396)(S6+O4)33·6H2O
Approval year:
2008

Classification of FantappièiteHide

Strunz-mindat (2026):
9.FB.05

9 : SILICATES (Germanates)
F : Tektosilicates without zeolitic H2O
B : Tektosilicates with additional anions
Dana 8th ed.:
76.2.9.20

76 : TECTOSILICATES Al-Si Framework
2 : Al-Si Framework Feldspathoids and related species

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
FtpIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of FantappièiteHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
Colorless
Streak:
White
Hardness:
6 on Mohs scale
Hardness:
VHN10=719 kg/mm2 - Vickers
Tenacity:
Brittle
Cleavage:
Poor/Indistinct
{001}
Parting:
none
Fracture:
Conchoidal
Density:
2.471 g/cm3 (Calculated)

Optical Data of FantappièiteHide

Type:
Uniaxial (-)
RI values:
nω = 1.5046(5) nε = 1.5027(5)
Max. Birefringence:
δ = 0.002
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.

Surface Relief:
Moderate (negative)
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.
Pleochroism:
Non-pleochroic

Chemistry of FantappièiteHide

Mindat Formula:
[Na82.5Ca33K16.5](Si99Al99O396)(SO4)33 · 4H2O
Element Weights:
Element% weight
O45.050 %
Si14.716 %
Al14.138 %
Na10.039 %
Ca7.000 %
S5.601 %
K3.414 %
H0.043 %

Calculated from ideal end-member formula.
O
Si
Al
Na
Ca
S
K
H
Elements listed:
Al, Ca, H, K, Na, O, S, Si - search for minerals with similar chemistry

Crystallography of FantappièiteHide

Crystal System:
Trigonal
Class (H-M):
3 - Rhombohedral
Space Group:
R3
Cell Parameters:
a = 12.8742(6) Å, c = 87.215(3) Å
Ratio:
a:c = 1 : 6.774
Unit Cell V:
12,518.79 ų (Calculated from Unit Cell)
Z:
1

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
6.85 Å(66)
6.39 Å(65)
5.74 Å(52)
3.773 Å(60)
3.691 Å(100)
3.587 Å(70)
3.551 Å(53)
2.639 Å(73)
Locality:
Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4b: Highly evolved igneous rocks>3.0
35 : Ultra-alkali and agpaitic igneous rocks

Type Occurrence of FantappièiteHide

Type Locality:
ⓘ Stracciacappe caldera, Metropolitan City of Rome Capital, Lazio, Italy
General Appearance of Type Material:
crystals, showing complex short-prismatic morphology
Place of Conservation of Type Material:
Museum of Mineralogy of the University of Roma, La Sapienza (code number MMUR 33027/1).
Geological Setting of Type Material:
In miarolytic cavities in volcanic ejectum consisting of dominant sanidine with minor plagioclase, biotite, augitic clinopyroxene, andradite, and iron oxides. y latestage metasomatic processes related to the phreatomagmatic stage of the Stracciacappe vent
Associated Minerals at Type Locality:
AndraditeAugiteBiotite

Synonyms of FantappièiteHide

Other Language Names for FantappièiteHide

Relationship of Fantappièite to other SpeciesHide

Member of:
Cancrinite Group > Feldspathoid Group
Other Members of Cancrinite Group:
Afghanite(Na,K)22Ca10(Si24Al24O96)(SO4)6Cl6Trig. 3m : P31c
Alloriite(Na,Ca,K)26Ca4(Al6Si6O24)4(SO4)6Cl6Trig. 3m : P31c
Balliranoite(Na,K)6Ca2(Si6Al6O24)Cl2(CO3)Hex. 6 : P63
BetziteNa6Ca2(Al6Si6O24)Cl4Hex. 6 : P63
Biachellaite(Na,Ca,K)8(Al6Si6O24)(SO4)2(OH)0.5 · H2OTrig. 3 : P3
Bystrite(Na,K)7Ca(Al6Si6O24)(S5)ClTrig. 3m : P31c
Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2OHex. 6 : P63
CancrisiliteNa7(Al5Si7O24)(CO3) · 3H2OHex. 6mm : P63mc
CarbobystriteNa8(Al6Si6O24)(CO3) · 3.5H2OTrig. 3m : P31c
Davyne(Na,K)6Ca2(Al6Si6O24)(Cl2,SO4)2Hex. 6/m : P63/m
DepmeieriteNa8(Al6Si6O24)(PO4,CO3)1-x · 3H2O (x<0.5)Hex. 6 : P63
Farneseite(Na,Ca,K)56(Al6Si6O24)7(SO4)12 · 6H2OHex. 6/m : P63/m
Franzinite(Na,K)6Ca2(Al6Si6O24)(SO4)2 · 0.5H2OHex.
Giuseppettite(Na,K,Ca)7-8(Al6Si6O24)(SO4,Cl)1-2Trig. 3m : P31c
HydroxycancriniteNa8(Al6Si6O24)(OH)2 · 2H2OHex. 6 : P63
KircheriteNa5Ca2K(Al6Si6O24)(SO4)2 · 0.33H2OTrig. 32 : R32
KyanoxaliteNa7(Al6-xSi6+xO24)(C2O4)0.5+x · 5H2O (0 < x < 0.5)Hex. 6 : P63
Liottite(Na,K)16Ca8(Al6Si6O24)3(SO4)5Cl4Hex. 6 : P6
Marinellite(Na,K)42Ca6(Al6Si6O24)6(SO4)8Cl2 · 3H2OTrig. 3m : P31c
MicrosommiteNa4K2Ca2(Al6Si6O24)(SO4)Cl2Hex. 622 : P6322
PitiglianoiteNa6K2(Al6Si6O24)(SO4) · 2H2OHex. 6 : P63
Quadridavyne(Na,K)6Ca2(Al6Si6O24)Cl4Hex. 6/m : P63/m
Sacrofanite(Na61K19Ca32)(Si84Al84O336)(SO4)26Cl2F6 · 2H2OHex.
SteudeliteNa3(K17Ca7)Ca4(Al24Si24O96)(SO3)6F6 · 4H2OHex. 6m2 : P62c
SulfhydrylbystriteNa5K2Ca[Al6Si6O24](S5)2(SH)Trig. 3m : P31c
Tounkite(Na,Ca,K)8(Si6Al6)O24(SO4)2Cl · 0.5H2OHex. 622 : P6222
'UM2004-48-SiO:AlClCaNaS'(Na,Ca)8(Si6Al6)O24(SO4)1.7Cl1.3
'UM2009-23-SiO:AlCCaClHKNaS'(Na,Ca)24K10[(Si,Al)60O120](SO4)5.6Cl1.5(CO3)0.4 · 11H2OTrig. 3 : P3
Vishnevite(Na,K)8(Al6Si6O24)(SO4,CO3) · 2H2OHex. 6 : P63

Common AssociatesHide

Associations Based on Photo Data:
2 photos of Fantappièite associated with Augite(CaxMgyFez)(Mgy1Fez1)Si2O6

Related Minerals - Strunz-mindat GroupingHide

9.FB.Perchukite-(Y)PbYAsSi2O8Mon. 2/m : B2/b
9.FB.Åsgruvanite-(Ce)Ce16Ca5Al(SiO4)6(AsO3)8(CO3)2Cl4F3(OH)2Trig. 3m(32/m) : P3m1
9.FB.SteudeliteNa3(K17Ca7)Ca4(Al24Si24O96)(SO3)6F6 · 4H2OHex. 6m2 : P62c
9.FB.Wenlanzhangite-(Y)Y2V3+2V4+2(SiO4)2O4(OH)4Tric. 1 : P1
9.FB.SlyudyankaiteNa28Ca4(Si24Al24O96)(SO4)6(S6)1/3(CO2) · 2H2OTric. 1 : P1
9.FB.Bolotinaite(Na7◻)(Al6Si6O24)F · 4H2OIso. 43m : I43m
9.FB.SapozhnikoviteNa8(Al6Si6O24)(HS)2Iso. 43m : P43n
9.FB.BetziteNa6Ca2(Al6Si6O24)Cl4Hex. 6 : P63
9.FB.05Quadridavyne(Na,K)6Ca2(Al6Si6O24)Cl4Hex. 6/m : P63/m
9.FB.05SulfhydrylbystriteNa5K2Ca[Al6Si6O24](S5)2(SH)Trig. 3m : P31c
9.FB.05Marinellite(Na,K)42Ca6(Al6Si6O24)6(SO4)8Cl2 · 3H2OTrig. 3m : P31c
9.FB.05Afghanite(Na,K)22Ca10(Si24Al24O96)(SO4)6Cl6Trig. 3m : P31c
9.FB.05Bystrite(Na,K)7Ca(Al6Si6O24)(S5)ClTrig. 3m : P31c
9.FB.05Franzinite(Na,K)6Ca2(Al6Si6O24)(SO4)2 · 0.5H2OHex.
9.FB.05KyanoxaliteNa7(Al6-xSi6+xO24)(C2O4)0.5+x · 5H2O (0 < x < 0.5)Hex. 6 : P63
9.FB.05Vishnevite(Na,K)8(Al6Si6O24)(SO4,CO3) · 2H2OHex. 6 : P63
9.FB.05Farneseite(Na,Ca,K)56(Al6Si6O24)7(SO4)12 · 6H2OHex. 6/m : P63/m
9.FB.05Alloriite(Na,Ca,K)26Ca4(Al6Si6O24)4(SO4)6Cl6Trig. 3m : P31c
9.FB.05Liottite(Na,K)16Ca8(Al6Si6O24)3(SO4)5Cl4Hex. 6 : P6
9.FB.05DepmeieriteNa8(Al6Si6O24)(PO4,CO3)1-x · 3H2O (x<0.5)Hex. 6 : P63
9.FB.05Biachellaite(Na,Ca,K)8(Al6Si6O24)(SO4)2(OH)0.5 · H2OTrig. 3 : P3
9.FB.05Cancrinite(Na,Ca,◻)8(Al6Si6O24)(CO3,SO4)2 · 2H2OHex. 6 : P63
9.FB.05CancrisiliteNa7(Al5Si7O24)(CO3) · 3H2OHex. 6mm : P63mc
9.FB.05CarbobystriteNa8(Al6Si6O24)(CO3) · 3.5H2OTrig. 3m : P31c
9.FB.05MicrosommiteNa4K2Ca2(Al6Si6O24)(SO4)Cl2Hex. 622 : P6322
9.FB.05PitiglianoiteNa6K2(Al6Si6O24)(SO4) · 2H2OHex. 6 : P63
9.FB.05Tounkite(Na,Ca,K)8(Si6Al6)O24(SO4)2Cl · 0.5H2OHex. 622 : P6222
9.FB.05Balliranoite(Na,K)6Ca2(Si6Al6O24)Cl2(CO3)Hex. 6 : P63
9.FB.05Giuseppettite(Na,K,Ca)7-8(Al6Si6O24)(SO4,Cl)1-2Trig. 3m : P31c
9.FB.05Sacrofanite(Na61K19Ca32)(Si84Al84O336)(SO4)26Cl2F6 · 2H2OHex.
9.FB.05KircheriteNa5Ca2K(Al6Si6O24)(SO4)2 · 0.33H2OTrig. 32 : R32
9.FB.05HydroxycancriniteNa8(Al6Si6O24)(OH)2 · 2H2OHex. 6 : P63
9.FB.05Davyne(Na,K)6Ca2(Al6Si6O24)(Cl2,SO4)2Hex. 6/m : P63/m
9.FB.10HaüyneNa3Ca(Si3Al3)O12(SO4)Iso. 43m : P43n
9.FB.10LazuriteNa7Ca(Al6Si6O24)(SO4)(S3) · H2OIso. 43m : P43n
9.FB.10DanaliteBe3Fe2+4(SiO4)3SIso. 43m : P43n
9.FB.10HelvineBe3Mn2+4(SiO4)3SIso. 43m : P43n
9.FB.10KamaishiliteCa2(Al2SiO6)(OH)2Tet.
9.FB.10SodaliteNa4(Si3Al3)O12ClIso. 43m : P43n
9.FB.10NoseanNa8(Al6Si6O24)(SO4) · H2OIso. 43m : P43n
9.FB.10GenthelviteBe3Zn4(SiO4)3SIso. 43m : P43n
9.FB.10BicchuliteCa2(Al2SiO6)(OH)2Iso. 43m : I43m
9.FB.10Tsaregorodtsevite(N(CH3)4)(AlSi5O12)Orth. 222 : I222
9.FB.10VladimirivanoviteNa6Ca2(Al6Si6O24)(SO4,S3,S2,Cl)2 · H2OOrth. mmm(2/m2/m2/m)
9.FB.10Tugtupite(BeAlSi)Na4(SiO4)3ClTet. 4 : I4
9.FB.15MarialiteNa4Al3Si9O24ClTet. 4/m : I4/m
9.FB.15MeioniteCa4Al6Si6O24CO3Tet. 4/m : I4/m
9.FB.15Silvialite(Ca,Na)4(Al6Si6O24)(SO4,CO3)Tet. 4/m : I4/m

RadioactivityHide

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) 3.4144% 1,058 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: –

DistanceDose rateRisk
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

Fluorescence of FantappièiteHide

Other InformationHide

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 FantappièiteHide

References for FantappièiteHide

Localities for FantappièiteHide

Showing 3 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
Hide all sections | Show all sections

Locality ListHide

- 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). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Italy (TL)
 
  • Lazio
    • Metropolitan City of Rome Capital
Bellatreccia et al. (2010)
Cundari (1979) +9 other references
    • Viterbo Province
      • Farnese
Antonio Borrelli collection (FTIR + XRD analysed - Università degli Studi Roma Tre)
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