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Tinaksite

A valid IMA mineral species
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02268630017271927076539.jpg
Tinaksite, etc.

Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
09967210017271927092513.jpg
Tinaksite, etc.

Apatitovyi Tsirk, Rasvumchorr Mine, Rasvumchorr Mt, Murmansk Oblast, Russia
04732190017271927147526.jpg
Tinaksite

Grozovoi area, Sirenevyi Kamen' Deposit, Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
02268630017271927076539.jpg
Tinaksite, etc.

Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
09967210017271927092513.jpg
Tinaksite, etc.

Apatitovyi Tsirk, Rasvumchorr Mine, Rasvumchorr Mt, Murmansk Oblast, Russia
04732190017271927147526.jpg
Tinaksite

Grozovoi area, Sirenevyi Kamen' Deposit, Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
02268630017271927076539.jpg
Tinaksite, etc.

Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
09967210017271927092513.jpg
Tinaksite, etc.

Apatitovyi Tsirk, Rasvumchorr Mine, Rasvumchorr Mt, Murmansk Oblast, Russia
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About TinaksiteHide

Formula:
K2Na(Ca,Mn2+)2TiO[Si7O18(OH)]
Colour:
Yellowish, grayish-white
Lustre:
Vitreous
Hardness:
6
Specific Gravity:
2.82 - 2.90
Crystal System:
Triclinic
Name:
The name reflects its composition: titanium (Ti), sodium (Na) potassium (K) and silicon (Si).
Isostructural with:
Tokkoite
The K analogue of senkevichite. Chemically somewhat similar to faizievite and odintsovite. When compared to tokkoite, it has smaller lattice constants (mainly the parameter b), shorter distances, shorter M1-M3 and O20-O2 bonds, and less distorted M1 polyhedron. There is some Fe3+ in the structure.


Unique IdentifiersHide

Mindat ID:
3966
Long-form identifier:
mindat:1:1:3966:2

Similar NamesHide

TungusiteA valid IMA mineral speciesCa4Fe2Si6O15(OH)6

IMA Classification of TinaksiteHide

IMA status:
Approved
IMA Formula:
K2NaCa2Ti4+Si7O18(OH)O
First published:
1965

Classification of TinaksiteHide

Strunz-mindat (2026):
9.DG.75

9 : SILICATES (Germanates)
D : Inosilicates
G : Inosilicates with 3-periodic single and multiple chains
Dana 8th ed.:
67.2.1.1

67 : INOSILICATES Unbranched Chains with W > 2
2 : Unbranched Chains with W>2 with W=5
Hey's CIM Ref.:
14.9.36

14 : Silicates not Containing Aluminum
9 : Silicates of Ti

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

Physical Properties of TinaksiteHide

Lustre:
Vitreous
Transparency:
Transparent, Translucent
Colour:
Yellowish, grayish-white
Hardness:
6 on Mohs scale
Cleavage:
Perfect
Perfect on {010}, imperfect on {110}; (010) ∧ (110) =
131.5°.
Density:
2.82 - 2.90 g/cm3 (Measured)    2.85 g/cm3 (Calculated)

Optical Data of TinaksiteHide

Type:
Biaxial (+)
RI values:
nα = 1.593 nβ = 1.621 nγ = 1.666
Max. Birefringence:
δ = 0.073
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:
High (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 biaxial acute bisectrix (Bxa) interference figure - the conoscopic view for a grain cut perpendicular to the acute bisectrix, using this mineral's 2V. The two small white dots mark the melatopes - the points where the two optic axes emerge - and are shown only when they fall within the field of view. The coloured bands are isochromatics, and the dark bands are isogyres.

Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.

No measured or calculated 2V is on file for this mineral, so the value used here (78°) is estimated from its recorded refractive indices and optic sign, not from a direct 2V measurement.
Dispersion:
none
Optical Extinction:
X' ∧ {010} = 1°-4°; Y ∧ {010} = 16°-18°.

Chemistry of TinaksiteHide

Mindat Formula:
K2Na(Ca,Mn2+)2TiO[Si7O18(OH)]
Element Weights:
Element% weight
O42.848 %
Si26.325 %
Ca10.733 %
K10.471 %
Ti6.410 %
Na3.078 %
H0.135 %

Calculated from ideal end-member formula.
O
Si
Ca
K
Ti
Na
H
Elements listed:
Ca, H, K, Mn, Na, O, Si, Ti - search for minerals with similar chemistry
Common Impurities:
Al,Fe,Mg,H2O

Crystallography of TinaksiteHide

Crystal System:
Triclinic
Cell Parameters:
a = 10.37 Å, b = 12.16 Å, c = 7.05 Å
α = 90.91°, β = 99.31°, γ = 92.76°
Ratio:
a:b:c = 0.853 : 1 : 0.58
Unit Cell V:
876.02 ų (Calculated from Unit Cell)
Comment:
Mean parameters concerning the structure refinement (Lacalamita et al., 2016): a~10.373, b~12.176, c~7.057, α~90.82, β~99.22, γ~92.80, V~878.5

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0009701TinaksiteBissert G (1980) Verfeinerung der struktur von tinaksit, Ca2K2NaTiO[Si7O18(OH)] Acta Crystallographica B36 259-26319800293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.03 Å(100)
3.25 Å(80)
2.331 Å(55)
3.09 Å(50)
2.952 Å(50)
2.865 Å(50)
2.674 Å(45)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
High-? alteration and/or metamorphism
31 : Thermally altered carbonate, phosphate, and iron formations

Type Occurrence of TinaksiteHide

Type Locality:
ⓘ Murunskii Massif, Chara and Tokko Rivers Confluence, Aldan Shield, Russia
General Appearance of Type Material:
Well-bounded prismatic crystals from tenths of a mm to several cm, often grouped in radiating fibrous aggregates and rosettes up to 3-5 cm in diameter.
Place of Conservation of Type Material:
n.d.
Geological Setting of Type Material:
K-feldspar metasomatites at the contact of the massif with limestones.
Associated Minerals at Type Locality:
AegirineCanasiteK FeldsparQuartzXonotlite

Other Language Names for TinaksiteHide

Dutch:Tinaksiet
German:Tinaksit
Spanish:Tinaksita

Common AssociatesHide

Associations Based on Photo Data:
115 photos of Tinaksite associated with Charoite(K,Sr)15-16(Ca,Na)32[Si6O11(O,OH)6]2[Si12O18(O,OH)12]2[Si17O25(O,OH)18]2(OH,F)4 · ~3H2O
78 photos of Tinaksite associated with AegirineNaFe3+Si2O6
7 photos of Tinaksite associated with FrankameniteK3Na3Ca5(Si12O30)(F,OH)4 · H2O
7 photos of Tinaksite associated with QuartzSiO2
6 photos of Tinaksite associated with Fedorite(Na,K)2-3(Ca4Na3)Si16O38(OH,F)2 · 3.5H2O
3 photos of Tinaksite associated with CanasiteK3Na3Ca5Si12O30(OH)4
2 photos of Tinaksite associated with 'Charoitite'
2 photos of Tinaksite associated with PectoliteNaCa2Si3O8(OH)
2 photos of Tinaksite associated with Magnesio-arfvedsoniteNaNa2(Mg4Fe3+)(Si8O22)(OH)2
2 photos of Tinaksite associated with 'Strontioburbankite'Na2Ca2Sr2[CO3]5

Related Minerals - Strunz-mindat GroupingHide

9.DG.Barrydawsonite-(Y)Na1.5Y0.5CaSi3O8(OH)Mon. 2/m : P21/c
9.DG.ParatobermoriteCa5AlSi5O16(OH) · 5H2OMon. 2/m
9.DG.CalcinaksiteKNaCa(Si4O10) · H2OTric. 1 : P1
9.DG.AlvesiteNaKZrSi6O15 · 2H2OOrth. mmm(2/m2/m2/m)
9.DG.02SteedeiteNaMn2[Si3BO9](OH)2Tric. 1 : P1
9.DG.02NolzeiteNaMn2[Si3BO9](OH)2 · 2H2OTric. 1 : P1
9.DG.05MurakamiiteLiCa2Si3O8(OH)Tric. 1 : P1
9.DG.05SeranditeNaMn2+2Si3O8(OH)Tric. 1 : P1
9.DG.05BustamiteCaMn2+(Si2O6)Tric. 1 : P1
9.DG.05PectoliteNaCa2Si3O8(OH)Tric. 1 : P1
9.DG.05TanohataiteLiMn2Si3O8(OH)Tric. 1 : P1
9.DG.05DalnegorskiteCa5Mn2+(Si3O9)2Tric. 1 : P1
9.DG.05'Wollastonite-1A'CaSiO3Tric. 1 : P1
9.DG.05WollastoniteCa3(Si3O9)Tric. 1 : P1
9.DG.05FerrobustamiteCaFe2+(Si2O6)Tric. 1
9.DG.05SchizoliteNaCaMnSi3O8(OH)Tric. 1 : P1
9.DG.07CascanditeCaScSi3O8(OH)Tric. 1
9.DG.08PlombièriteCa5Si6O16(OH)2 · 7H2OOrth.
9.DG.10ClinotobermoriteCa5Si6O17 · 5H2OMon.
9.DG.10RiversideiteCa5Si6O16(OH)2 · 2H2O Orth.
9.DG.10TobermoriteCa5Si6O17 · 5H2OMon. 2 : P21
9.DG.12JusiteNa2Ca15Al4Si16O54 · 17H2O
9.DG.12KenotobermoriteCa4Si6O15(OH)2 · 5H2OMon.
9.DG.15FoshagiteCa4(Si3O9)(OH)2Tric. 1 : P1
9.DG.20JenniteCa9(Si3O9)2(OH)8 · 8H2OTric. 1 : P1
9.DG.20KameneviteK2TiSi3O9 · H2OOrth. 222 : P212121
9.DG.25ParaumbiteK3Zr2H(Si3O9)2 · nH2OOrth. mm2
9.DG.25UmbiteK2(Zr,Ti)Si3O9 · H2OOrth. 222 : P212121
9.DG.30SørenseniteNa4SnBe2Si6O16(OH)4Mon. 2/m : B2/b
9.DG.32Escheite Ca2NaMnTi5[Si12O34]O2(OH)3 · 12H2OOrth. mm2 : Ama2
9.DG.35XonotliteCa6(Si6O17)(OH)2Mon. 2/m : B2/m
9.DG.40HillebranditeCa2(SiO3)(OH)2Orth. mmm(2/m2/m2/m) : Cmcm
9.DG.45ZoriteNa8(Ti,Nb)5(Si6O17)2(OH,O)5 · 14H2OOrth.
9.DG.45ChivruaiiteCa4(Ti,Nb)5(Si6O17)2(OH,O)5 · 13-14H2OOrth. mmm(2/m2/m2/m) : Cmmm
9.DG.50Haineaultite(Na,Ca)5Ca(Ti,Nb)5(Si6O17)2(OH,F)8 · 5H2OOrth. 222 : C222
9.DG.55EpididymiteNa2Be2Si6O15 · H2OOrth. mmm(2/m2/m2/m) : Pnma
9.DG.60EudidymiteNa2Be2Si6O15 · H2OMon. 2/m : B2/b
9.DG.65ElpiditeNa2ZrSi6O15 · 3H2OOrth.
9.DG.65PatyniteNaKCa4[Si9O23]Tric. 1 : P1
9.DG.67WhelaniteCu2+2Ca6[Si6O17(OH)](CO3)(OH)3 · 2H2OOrth. mm2 : Pnn2
9.DG.70EnricofrancoiteKNaCaSi4O10Tric. 1 : P1
9.DG.70YusupoviteNa2Zr(Si6O15) · 2.5H2OMon. 2/m : B2/m
9.DG.70LitidioniteKNaCuSi4O10Tric. 1 : P1
9.DG.70Fenaksite(K,Na)4(Fe,Mn)2(Si4O10)2(OH,F)Tric. 1 : P1
9.DG.70ManaksiteKNaMnSi4O10Tric. 1 : P1
9.DG.75SenkevichiteCsKNaCa2TiO[Si7O18](OH)Tric. 1 : P1
9.DG.75TokkoiteK2Ca4[Si7O18(OH)](OH,F)Tric.
9.DG.80FluorcanasiteK3Na3Ca5Si12O30F4 · H2OMon. m : Bm
9.DG.80CanasiteK3Na3Ca5Si12O30(OH)4Mon. m : Bm
9.DG.85MiseriteK1.5-x(Ca,Y,REE)5(Si6O15)(Si2O7)(OH,F)2 · yH2OTric.
9.DG.90FrankameniteK3Na3Ca5(Si12O30)(F,OH)4 · H2OTric. 1 : P1
9.DG.92Charoite(K,Sr)15-16(Ca,Na)32[Si6O11(O,OH)6]2[Si12O18(O,OH)12]2[Si17O25(O,OH)18]2(OH,F)4 · ~3H2OMon. 2/m : P21/m
9.DG.95YuksporiteK4(Ca,Na)14(Sr,Ba)2(◻,Mn,Fe)(Ti,Nb)4(O,OH)4(Si6O17)2(Si2O7)3(H2O,OH)3Mon. 2/m : P21/m
9.DG.97Eveslogite(Na,K,Ca,Sr,Ba)48 [(Ti,Nb,Mn,Fe2+)12Si48O144(OH)12](F,OH,Cl)14Mon. 2/m : P2/c

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) 10.4708% 3,246 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

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.

Tinaksite in petrologyHide

An essential component of rock names highlighted in red, an accessory component in rock names highlighted in green.

Internet Links for TinaksiteHide

References for TinaksiteHide

Localities for TinaksiteHide

Showing 12 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.
Russia (TL)
 
  • Aldan Shield
    • Chara and Tokko Rivers Confluence
Konev et al. (1993) +2 other references
Kaneva +4 other references
Pavel M. Kartashov (n.d.) +3 other references
- (n.d.)
Konev et al. (1996) +1 other reference
Vorob'yov E.I. (2008)
Vorob'yov E.I. (2008)
Pavel M. Kartashov (n.d.)
  • Irkutsk Oblast
Vladykin et al. (2008)
  • Murmansk Oblast
    • Carbonatite Stock in the vicinity of Tul'ilukht Bay
Mandarino (1997)
    • Rasvumchorr Mt
      • Rasvumchorr Mine
Pavel M. Kartashov (n.d.)
Saudi Arabia
 
  • Medina Region
Faheha et al. (2012)
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