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Yagiite

A valid IMA mineral species
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05676800017271927646834.jpg
Kenzo Yagi
Formula:
Na◻2Mg2Al3[Al2Si10O30]
IMA formula given as: Na◻2Mg2(AlMg2)[Si12O30], which does indeed charge-balance.

Gagné & Hawthorne (2016) report an alternative and also charge-balanced formula, which eliminates Mg from the T2 site: Na◻2Mg2Al3[Al2Si10O30].

The actual formula based on the reported oxide%, normalized to T1+T2+A = 17, corresponds to: (Na1.19K0.301.51)(Mg1.55Fe2+0.20Fe3+0.13Ti0.10Ca0.02)(Al1.96Mg1.04)[Al1.77Si10.23O30], which approximately reduces to the charge-balanced formula: Na(◻Na)Mg2(Al2Mg)[Al2Si10O30]. This formula shows a T2 site mix of Al and Mg intermediate between the IMA and Gagné & Hawthorne (2016) formulas, but requires an extra 1+ cation to charge balance (hence the B site as (◻Na) instead of ◻2 as per the other formulas).

Although not entirely consistent with the natural composition, the formula of Gagné & Hawthorne 2016 is presented as our "mindat" formula for this mineral.

Colour:
Colourless
Hardness:
5 - 6
Specific Gravity:
2.70 (Calculated)
Crystal System:
Hexagonal
Member of:
Name:
Named by Theodore E. Bunch and Louis H. Fuchs in 1969 in honor of Kenzo Yagi (15 September 1915, Nagano City, Nagano Prefecture, Japan - 18 July 2008), Professor of Geology, Hokkaido University, Sapporo, Japan for his contributions to mineralogy and petrology.
Na-dominant member of the osumilite group.


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Unique IdentifiersHide

Mindat ID:
4350
Long-form identifier:
mindat:1:1:4350:8

Similar NamesHide

AugiteA valid IMA mineral species - grandfathered(CaxMgyFez)(Mgy1Fez1)Si2O6
Uigite

IMA Classification of YagiiteHide

Approved
IMA Formula:
NaMg2(AlMg2Si12)O30
Approval year:
1968
First published:
1969

Classification of YagiiteHide

9.CM.05

9 : SILICATES (Germanates)
C : Cyclosilicates
M : [Si6O18]12- 6-membered double rings (sechser-Doppelringe)
63.2.1a.10

63 : CYCLOSILICATES Condensed Rings
2 : Condensed Rings (Milarite - Osumilite group)
16.8.5

16 : Silicates Containing Aluminum and other Metals
8 : Aluminosilicates of Mg and alkalis

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

Physical Properties of YagiiteHide

Transparency:
Translucent
Colour:
Colourless
Comment:
Can be very light blue in thin section
Hardness:
5 - 6 on Mohs scale
Density:
2.70 g/cm3 (Calculated)

Optical Data of YagiiteHide

Type:
Uniaxial (+)
RI values:
nω = 1.536(2) nε = 1.544(2)
Max. Birefringence:
δ = 0.008
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.

Surface Relief:
Moderate
Pleochroism:
Weak
Comments:
O = very light blue; E = colorless

Chemistry of YagiiteHide

Mindat Formula:
Na◻2Mg2Al3[Al2Si10O30]

IMA formula given as: Na◻2Mg2(AlMg2)[Si12O30], which does indeed charge-balance.

Gagné & Hawthorne (2016) report an alternative and also charge-balanced formula, which eliminates Mg from the T2 site: Na◻2Mg2Al3[Al2Si10O30].

The actual formula based on the reported oxide%, normalized to T1+T2+A = 17, corresponds to: (Na1.19K0.301.51)(Mg1.55Fe2+0.20Fe3+0.13Ti0.10Ca0.02)(Al1.96Mg1.04)[Al1.77Si10.23O30], which approximately reduces to the charge-balanced formula: Na(◻Na)Mg2(Al2Mg)[Al2Si10O30]. This formula shows a T2 site mix of Al and Mg intermediate between the IMA and Gagné & Hawthorne (2016) formulas, but requires an extra 1+ cation to charge balance (hence the B site as (◻Na) instead of ◻2 as per the other formulas).

Although not entirely consistent with the natural composition, the formula of Gagné & Hawthorne 2016 is presented as our "mindat" formula for this mineral.

Element Weights:
Element% weight
O49.619 %
Si29.034 %
Al13.946 %
Mg5.025 %
Na2.377 %

Calculated from ideal end-member formula.
Common Impurities:
Ti,Cr,Fe,Mn,Ca

Crystallography of YagiiteHide

Crystal System:
Hexagonal
Class (H-M):
6/mmm(6/m2/m2/m) - Dihexagonal Dipyramidal
Space Group:
P6/mcc
Setting:
P6/mcc
Cell Parameters:
a = 10.09(1) Å, c = 14.29(3) Å
Ratio:
a:c = 1 : 1.416
Unit Cell V:
1,259.93 ų (Calculated from Unit Cell)
Z:
2

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.228 Å(100)
5.059 Å(65)
3.726 Å(50)
2.765 Å(50)
2.090 Å(40)
7.12 Å(30)
2.003 Å(30)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 2: Planetesimal differentiation and alteration4.566-4.550
5 : Primary asteroid phases4.566–4.560

Type Occurrence of YagiiteHide

General Appearance of Type Material:
Interstitial to small equant grains.
Geological Setting of Type Material:
Silicate inclusions in an iron meteorite.
Associated Minerals at Type Locality:

Synonyms of YagiiteHide

Other Language Names for YagiiteHide

Relationship of Yagiite to other SpeciesHide

Member of:
Other Members of Osumilite Group:
Agakhanovite-(Y)K◻2(YCa)Be3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
AlmaruditeK◻2Mn2+2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mmm
AluminosugiliteKNa2Al2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
ArmeniteBa(H2O)2Ca2Al3[Al3Si9O30]Orth. mmm(2/m2/m2/m) : Pnna
BerezanskiteK◻2Ti2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
BrannockiteK◻2Sn2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
ChayesiteK◻2Mg2(Mg2Fe3+)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
DarapiositeKNa2Mn2(Zn2Li)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
DusmatoviteK(K◻)Mn2+2Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
EifeliteKNa2(MgNa)Mg3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
FriedrichbeckeiteK(◻Na)Mg2(Be2Mg)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
KlöchiteK◻2(Fe2+Fe3+)Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P63/mmc
LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
MerrihueiteK(◻Na)Fe2+2Fe2+3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
MilariteK(◻H2O)Ca2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
OftedaliteK◻2(ScCa)Be3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
OsumiliteK◻2Fe2+2Al3[Al2Si10O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
Osumilite-(Mg)K◻2Mg2Al3[Al2Si10O30] Hex. 6/mmm(6/m2/m2/m) : P6/mcc
PlechoviteCa2[K(H2O)]KBe3Si12O30Hex. 6/mmm(6/m2/m2/m) : P6/mcc
PoudretteiteK◻2Na2B3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
RoedderiteK(◻Na)Mg2Mg3[Si12O30]Hex. 6m2 : P62c
ShibkoviteK(◻K)Ca2Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
SogdianiteK◻2Zr2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
SugiliteKNa2Fe3+2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
Trattnerite◻(◻)2Fe3+2Mg3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
'UM1990-73-SiO:KMnNaZn'K(KNa0.50.5)(Mn1.5Na0.5)Zn3[Si12O30]Hex.
'Unnamed (Mn3+-dominant analog of Sugilite)'KNa2Mn3+2Li3[Si12O30]

Related Minerals - Strunz-mindat GroupingHide

9.CM.Agakhanovite-(Y)K◻2(YCa)Be3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.PlechoviteCa2[K(H2O)]KBe3Si12O30Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05FriedrichbeckeiteK(◻Na)Mg2(Be2Mg)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05LaurentthomasiteK◻2Mg2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05'UM1990-73-SiO:KMnNaZn'K(KNa0.50.5)(Mn1.5Na0.5)Zn3[Si12O30]Hex.
9.CM.05EifeliteKNa2(MgNa)Mg3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05AlmaruditeK◻2Mn2+2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mmm
9.CM.05ArmeniteBa(H2O)2Ca2Al3[Al3Si9O30]Orth. mmm(2/m2/m2/m) : Pnna
9.CM.05MerrihueiteK(◻Na)Fe2+2Fe2+3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05OftedaliteK◻2(ScCa)Be3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05RoedderiteK(◻Na)Mg2Mg3[Si12O30]Hex. 6m2 : P62c
9.CM.05ShibkoviteK(◻K)Ca2Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05SogdianiteK◻2Zr2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05MilariteK(◻H2O)Ca2(Be2Al)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05BerezanskiteK◻2Ti2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05PoudretteiteK◻2Na2B3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05DarapiositeKNa2Mn2(Zn2Li)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05ChayesiteK◻2Mg2(Mg2Fe3+)[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05Osumilite-(Mg)K◻2Mg2Al3[Al2Si10O30] Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05OsumiliteK◻2Fe2+2Al3[Al2Si10O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05SugiliteKNa2Fe3+2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05Trattnerite◻(◻)2Fe3+2Mg3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05BrannockiteK◻2Sn2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.05KlöchiteK◻2(Fe2+Fe3+)Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P63/mmc
9.CM.05DusmatoviteK(K◻)Mn2+2Zn3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.9.CM.AluminosugiliteKNa2Al2Li3[Si12O30]Hex. 6/mmm(6/m2/m2/m) : P6/mcc
9.CM.10FaizieviteK2Na(Ca6Na)Ti4Li6[Si6O18]2[Si12O30]F2Tric. 1 : P1

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 YagiiteHide

References for YagiiteHide

Localities for YagiiteHide

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.
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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.
Japan
 
  • Aichi Prefecture
    • Tahara City
Miura et al. (1994)
Mexico
 
  • Zacatecas
    • Sombrerete Municipality
Ruzicka et al. (2006)
Spain (TL)
 
  • Andalusia
    • Granada
      • Colomera
[AM 54 (1969) +1 other reference
 
and/or  
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