Ilmajokite-(Ce)
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Ilmajokite-(Ce)
Formula:
Na11KBaCe2Ti12Si37.5O94(OH)31 · 29H2O
formerly given as (Na,Ce,Ba)2TiSi3O5(OH)10.nH2O and (Na,Ce,Ba)10Ti5Si14O22(OH)44.nH2O
Colour:
Bright yellow
Lustre:
Vitreous
Hardness:
1
Crystal System:
Monoclinic
Name:
Named for the Ilmajok River, Russia, located near the type locality. It was originally named simply ilmajokite and renamed in 2020 after new data showed a REE as a species-forming element. The new name follows the IMA nomenclature (Levinson rule) for REEs.
The crystal structure is based upon complex porous titanosilicate framework in which the SiO4 tetrahedra form a three-dimensional structure with a previously unknown topology.
Third (?) most structurally complex mineral after ewingite and morrisonite (also compare batoniite).
Structural complexity: 8.468 bits per atom; 11990.129 bits per cell.
The most complex mineral framework structure (complexity comparable to that of paulingite-Ca).
Compare heamanite-(Ce), that, however, is not a silicate but an oxide.
Third (?) most structurally complex mineral after ewingite and morrisonite (also compare batoniite).
Structural complexity: 8.468 bits per atom; 11990.129 bits per cell.
The most complex mineral framework structure (complexity comparable to that of paulingite-Ca).
Compare heamanite-(Ce), that, however, is not a silicate but an oxide.
Unique Identifiers
Mindat ID:
2012
Long-form identifier:
mindat:1:1:2012:7
GUID
(UUID V4):
(UUID V4):
4984d162-a8de-4ea3-917e-9f6665bd0d79
IMA Classification of Ilmajokite-(Ce)
Approved
IMA status notes:
Redefined by the IMA, Renamed by the IMA
IMA Formula:
Na11KBaCe2Ti12Si37.5O94(OH)30 · 29H2O
Approval year:
1971
First published:
1972
Approval history:
Approved as IMA1971-027, as Ilmajokite.
2019: Revised chemical formula as Na11KBaCe2Ti12Si37.5O94(OH)31·29H2O and renamed as Ilmajokite-(Ce). (CNMNC Newsletter 53)
2019: Revised chemical formula as Na11KBaCe2Ti12Si37.5O94(OH)31·29H2O and renamed as Ilmajokite-(Ce). (CNMNC Newsletter 53)
Classification of Ilmajokite-(Ce)
9.HB.05
9 : SILICATES (Germanates)
H : Unclassified silicates
B : With Ti, V, Cr
9 : SILICATES (Germanates)
H : Unclassified silicates
B : With Ti, V, Cr
78.7.5.1
78 : Unclassified Silicates
7 :
78 : Unclassified Silicates
7 :
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 |
|---|---|---|
| Ijk-Ce | 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 Ilmajokite-(Ce)
Vitreous
Transparency:
Transparent, Translucent
Colour:
Bright yellow
Hardness:
1 on Mohs scale
Tenacity:
Brittle
Cleavage:
Perfect
Optical Data of Ilmajokite-(Ce)
Type:
Biaxial (+)
RI values:
nα = 1.573 nβ = 1.576 nγ = 1.579
2V:
Measured: 90° , Calculated: 88°
Max Birefringence:
δ = 0.006
Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.
and does not take into account mineral colouration.
Surface Relief:
Low
Dispersion:
r < v strong
Chemistry of Ilmajokite-(Ce)
Mindat Formula:
Na11KBaCe2Ti12Si37.5O94(OH)31 · 29H2O
formerly given as (Na,Ce,Ba)2TiSi3O5(OH)10.nH2O and (Na,Ce,Ba)10Ti5Si14O22(OH)44.nH2O
formerly given as (Na,Ce,Ba)2TiSi3O5(OH)10.nH2O and (Na,Ce,Ba)10Ti5Si14O22(OH)44.nH2O
Common Impurities:
Zr,Al,TR,Fe,Nb,Ta,Ca,Sr,K,C
Crystallography of Ilmajokite-(Ce)
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/b
Setting:
C2/c
Cell Parameters:
a = 35.908(5) Å, b = 27.784(3) Å, c = 33.126(4) Å
β = 96.494(3)°
β = 96.494(3)°
Ratio:
a:b:c = 1.292 : 1 : 1.192
Unit Cell V:
32,836.70 ų (Calculated from Unit Cell)
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 11.5 Å | (100) |
| 10.9 Å | (70) |
| 10.2 Å | (90) |
| 4.3 Å | (100) |
| 3.7 Å | (70) |
| 3.1 Å | (90) |
| 2.44 Å | (100) |
Comments:
Lovozero massif, Russia. The data are from the type description.
Type Occurrence of Ilmajokite-(Ce)
General Appearance of Type Material:
Granular deposits, crusts, and brushes of crystals.
Place of Conservation of Type Material:
Geology Museum, Kola Branch, Academy of Sciences, Russia, 3152, 3153.
Mining Institute, St. Petersburg, Russia, 1061/1-2.
A.E. Fersman Mineralogical Museum, Academy of Sciences, Moscow, Russia, 74041, 74080, 74490, 74491.
National School of Mines, Paris, France.
Mining Institute, St. Petersburg, Russia, 1061/1-2.
A.E. Fersman Mineralogical Museum, Academy of Sciences, Moscow, Russia, 74041, 74080, 74490, 74491.
National School of Mines, Paris, France.
Geological Setting of Type Material:
Alkaline pegmatite.
Reference:
Bussen, I.V., Gannibal, L.F., Goiko, E.A., Mer'kov, A.N., Nedorezova, A.P. (1972) Ilmajokite, a new mineral from the Lovozero Tundra. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva: 101(1): 75-79.
Synonyms of Ilmajokite-(Ce)
Other Language Names for Ilmajokite-(Ce)
German:Ilmajokit
Spanish:Ilmajokita
Common Associates
Associated Minerals Based on Photo Data:
Related Minerals - Strunz-mindat Grouping
| 9.HB. | Waipouaite | Ca3V4+5O9[Si2O5(OH)2][Si3O7(OH)2] · 11H2O |
| 9.HB.10 | Rilandite | Cr6SiO11 · 5H2O (?) |
Other Information
Notes:
Decomposes in water at 20°C, giving amorphous silica and in acid, giving slight effervescence and amorphous silica gel.
Special Storage/
Display Requirements:
Display Requirements:
Unstable in ambient conditions.
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 Ilmajokite-(Ce)
mindat.org URL:
https://www.mindat.org/min-2012.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
Mineral Dealers:
References for Ilmajokite-(Ce)
Reference List:
Localities for Ilmajokite-(Ce)
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.
Russia (TL) | |
| Bussen et al. (1972) +3 other references |
Quick NavTopAbout Ilmajokite-(Ce)Unique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionType Occurrence SynonymsOther LanguagesCommon AssociatesStrunz-MindatOther InformationInternet Links References Localities Locality List
Yubileinaya pegmatite, Karnasurt Mountain, Lovozersky District, Murmansk Oblast, Russia