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Abenakiite-(Ce)

A valid IMA mineral species
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About Abenakiite-(Ce)Hide

02959260017271920828225.jpg
Abenaki Couple
Formula:
Na26Ce6(Si6O18)(PO4)6(CO3)6(SO2)O
Colour:
Pale brown
Lustre:
Vitreous
Hardness:
4 - 5
Specific Gravity:
3.21
Crystal System:
Trigonal
Name:
Named after the Abenaki, the indigenous people who inhabited the area around Mont Saint-Hilaire in southern Québec and the North-Eastern USA, prior to the arrival of European settlers. The suffix/modifier indicates that the predominant essential REE is cerium.
Unique chemistry (the only Na-REE-Si-P-C mineral). Chemistry comparable to that of steenstrupine-(Ce).

Currently the only mineral with a supposed sulphur dioxide inclusion. Originally a single grain was found, making the mineral exceedingly rare.

Hexagonal net of the structure contains (1) chains of NaO7 polyhedra connected with phosphate groups, (2) six-membered ring of SiO4, NaO7 and NaO7-(REE)O8 polyhedra, forming columns, (3) carbonate and SO2 groups, and NaO6 octahedra, within the columns. In terms of the linkage of six-member silicate ring and NaO6 octahedron, abenakiite-(Ce) may be compared to kazakovite and steenstrupine-(Ce) (McDonald et al., 1994).

Infrared data for an S-deficient and H2O-bearing variety or a related species from the Sirenevaya pegmatite is given by Chukanov (2014). The mineral occurs as a yellow-grey grain in ussingite, and its empirical formula is reported as (Na5.55K0.17Ca0.04)(Ce3.34La1.71Nd1.20Pr0.46Th0.12)(Si5.97P6.86S0.17)Ox(CO3)y.nH2O. This formula doesn't seem to correspond to abenakiite-(Ce) and no XRD data is given to confirm its identity with abenakiite-(Ce). The main IR bands obtained for this material are [cm-1]: 3390, 1580sh, 1520, 1140sh, 1070s, 902, 860sh, 615, and 448.


Unique IdentifiersHide

Mindat ID:
2
Long-form identifier:
mindat:1:1:2:4

IMA Classification of Abenakiite-(Ce)Hide

Classification of Abenakiite-(Ce)Hide

9.CK.10

9 : SILICATES (Germanates)
C : Cyclosilicates
K : [Si6O18]12- 6-membered single rings, with insular complex anions
Dana 7th ed.:
61.4.1.1
61.4.1.1

61 : CYCLOSILICATES Six-Membered Rings
4 : Six-Membered Rings with other anions

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

Physical Properties of Abenakiite-(Ce)Hide

Vitreous
Transparency:
Transparent
Colour:
Pale brown
Streak:
White
Hardness:
4 - 5 on Mohs scale
Tenacity:
Brittle
Cleavage:
Poor/Indistinct
{0001}
Fracture:
Conchoidal
Density:
3.21 g/cm3 (Measured)    3.27 g/cm3 (Calculated)

Optical Data of Abenakiite-(Ce)Hide

Type:
Uniaxial (-)
RI values:
nω = 1.589(1) nε = 1.586(1)
Max. Birefringence:
δ = 0.003
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 (positive)
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 Abenakiite-(Ce)Hide

Mindat Formula:
Na26Ce6(Si6O18)(PO4)6(CO3)6(SO2)O
Element Weights:
Element% weight
O34.699 %
Ce28.941 %
Na20.577 %
P6.398 %
Si5.801 %
C2.481 %
S1.104 %

Calculated from ideal end-member formula.
O
Ce
Na
P
Si
C
S

Chemical AnalysisHide

Oxide wt%:
 12345
Na2O25.04 %25.33 %25.52 %25.37 %25.32 %
Ce2O315.50 %15.36 %15.24 %15.15 %15.31 %
La2O36.08 %5.86 %6.11 %5.69 %5.94 %
Nd2O38.04 %8.07 %7.59 %7.41 %7.78 %
Pr2O31.91 %2.43 %1.95 %1.77 %2.02 %
Sm2O30.88 %0.78 %0.59 %0.70 %0.74 %
ThO21.86 %1.27 %1.21 %1.32 %1.42 %
SrO0.12 %0.13 %0.09 %0.13 %0.12 %
SiO213.71 %13.35 %13.00 %13.14 %13.30 %
P2O514.60 %14.09 %13.70 %14.05 %14.11 %
SO22.34 %2.34 %2.18 %2.28 %2.28 %
CO29.10 %8.95 %8.76 %8.82 %8.91 %
Total:99.18 %97.96 %95.94 %95.83 %97.25 %
Empirical formulas:
Sample IDEmpirical Formula
5 Na24.23(Ce2.77Nd1.37La1.08Pr0.36Th0.16Sm0.13Sr0.03)Σ5.90Si6.56P5.90C6S1.06O63
Sample references:
IDTypeLocalityReferenceNotes
1Type SpecimenPoudrette quarry, Mont Saint-Hilaire, La Vallée-du-Richelieu RCM, Montérégie, Québec, CanadaCO2 calculated from stoichiometry.
2Type Specimen  "  "CO2 calculated from stoichiometry.
3Type Specimen  "  "CO2 calculated from stoichiometry.
4Type Specimen  "  "CO2 calculated from stoichiometry.
5Average of analyses 1-4  "  "CO2 calculated from stoichiometry.

Crystallography of Abenakiite-(Ce)Hide

Crystal System:
Trigonal
Class (H-M):
3 - Rhombohedral
Space Group:
R3
Cell Parameters:
a = 16.018(2) Å, c = 19.761(2) Å
Ratio:
a:c = 1 : 1.234
Unit Cell V:
4,390.93 ų (Calculated from Unit Cell)
Z:
3

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0005409Abenakiite-(Ce)McDonald A M, Chao G Y, Grice J D (1994) Abenakiite-(Ce), a new silicophosphate carbonate mineral from Mont Saint-Hilaire, Quebec: description and structure determination The Canadian Mineralogist 32 843-8541994Mont Saint-Hilaire, Quebec, Canada0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
11.414 Å(75)
8.036 Å(85)
6.554 Å(85)
4.646 Å(75)
3.773 Å(90)
3.591 Å(80)
3.150 Å(70)
2.674 Å(100)

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 Abenakiite-(Ce)Hide

General Appearance of Type Material:
A single grain, 2 x 1 mm in size.
Place of Conservation of Type Material:
Canadian Museum of Nature, Ottawa, Ontario, Canada, #81501.
Geological Setting of Type Material:
In a xenolith of sodalite syenite. A late-stage phase, possibly arising from a metasomatic event associated with emplacement of the nepheline syenite.
Associated Minerals at Type Locality:

Synonyms of Abenakiite-(Ce)Hide

Other Language Names for Abenakiite-(Ce)Hide

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Abenakiite-(Ce) associated with UssingiteNa2AlSi3O8OH
1 photo of Abenakiite-(Ce) associated with SodaliteNa4(Si3Al3)O12Cl

Related Minerals - Strunz-mindat GroupingHide

9.CK.AdachiiteCaFe3Al6(Si5AlO18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.Magnesio-dutrowiteNa(Mg2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.DarrellhenryiteNa(Al2Li)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Fluor-schorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.PrincivalleiteNa(Mn2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Alumino-oxy-rossmanite◻Al3Al6(Si5AlO18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.DutrowiteNa(Fe2+2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Ferro-bosiiteNaFe3+3(Al4Fe2+2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.BosiiteNaFe3+3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.Celleriite◻(Mn2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05FeruviteCaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Chromium-draviteNaMg3Cr3+6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-rossmanite◻(Al2Li)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m(32/m) : R3m
9.CK.05Oxy-schorlNa(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-elbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05DraviteNaMg3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-uviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Foitite◻(Fe2+2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Vanadio-oxy-draviteNaV3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-buergeriteNaFe3+3Al6(Si6O18)(BO3)3O3FTrig. 3m : R3m
9.CK.05'Unnamed (F analogue of feruvite)'CaFe2+3(Al5Mg)(Si6O18)(BO3)3(OH)3F
9.CK.05ErtliteNaAl3Al6(Si4B2O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05TsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-liddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05UviteCaMg3(Al5Mg)(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05ElbaiteNa(Li1.5Al1.5)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Fluor-tsilaisiteNaMn2+3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Oxy-foitite◻(Fe2+Al2)Al6(Si6O18)(BO3)3(OH)3OTrig. 3m(32/m) : R3m
9.CK.05LiddicoatiteCa(Li2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Vanadio-oxy-chromium-draviteNaV3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O Trig. 3m : R3m
9.CK.05Rossmanite◻(LiAl2)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Oxy-vanadium-draviteNaV3(V4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05OleniteNaAl3Al6(Si6O18)(BO3)3O3(OH)Trig. 3m : R3m
9.CK.05'UM2000-64-SiO:BFeHKMg'(K,Na)Fe3+3(Mg2Fe3+4)Si6O18(BO3)3(OH)3O
9.CK.05Magnesio-lucchesiiteCaMg3Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05PovondraiteNaFe3+3(Mg2Fe3+4)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05LucchesiiteCaFe2+3 Al6(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Chromo-alumino-povondraiteNaCr3(Al4Mg2)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Fluor-draviteNaMg3Al6(Si6O18)(BO3)3(OH)3FTrig. 3m : R3m
9.CK.05Oxy-draviteNa(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.05Oxy-chromium-draviteNaCr3(Cr4Mg2)(Si6O18)(BO3)3(OH)3O Trig. 3m : R3m
9.CK.05'Luinaite-(OH)'NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)Mon. m : Bm
9.CK.05SchorlNaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05Magnesio-foitite◻(Mg2Al)Al6(Si6O18)(BO3)3(OH)3(OH)Trig. 3m : R3m
9.CK.05MaruyamaiteK(Al2Mg)(Al5Mg)(Si6O18)(BO3)3(OH)3OTrig. 3m : R3m
9.CK.15ScawtiteCa7(Si3O9)2CO3 · 2H2OMon. 2/m
9.CK.20Thorosteenstrupine(Ca,Th,Mn)3Si4O11F · 6H2O
9.CK.20Steenstrupine-(Ce)Na14Mn2+2Fe3+2Ce6Zr(Si6O18)2(PO4)6(PO3OH)(OH)2 · 2H2OTrig. 3m(32/m) : R3m

Fluorescence of Abenakiite-(Ce)Hide

Other InformationHide

Notes:
A very weak effervescence in 1:1 HCl.
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 Abenakiite-(Ce)Hide

References for Abenakiite-(Ce)Hide

Localities for Abenakiite-(Ce)Hide

Showing 2 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.
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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.
Canada (TL)
 
  • Québec
    • Montérégie
      • La Vallée-du-Richelieu RCM
        • Mont Saint-Hilaire
McDonald et al. (1994)
Russia
 
  • Murmansk Oblast
    • Lovozersky District
      • Alluaiv Mountain
        • Umbozero mine
Chukanov (2014)
 
and/or  
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