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Tassieite

A valid IMA mineral species
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Formula:
(Na,◻)Ca2(Mg,Fe2+,Fe3+)2(Fe2+,Mg)2(Fe3+,Mg)2(PO4)6 · 2H2O
Colour:
dark green
Lustre:
Vitreous
Specific Gravity:
3.45 (Calculated)
Crystal System:
Orthorhombic
Member of:
Wicksite Group
Name:
Named for type locality, Tassie Tarn, Stornes Peninsula, Larsemann Hills, Antarctica
Wicksite Group.


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Unique IdentifiersHide

Mindat ID:
29006
Long-form identifier:
mindat:1:1:29006:1

Similar NamesHide

IMA Classification of TassieiteHide

Classification of TassieiteHide

Strunz-mindat (2026):
8.CF.05

8 : PHOSPHATES, ARSENATES, VANADATES
C : Phosphates without additional anions, with H2O
F : With large and medium-sized cations, RO4:H2O > 1:1
Dana 8th ed.:
40.2.16.3

40 : HYDRATED NORMAL PHOSPHATES,ARSENATES AND VANADATES
2 : AB2(XO4)2·xH2O

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

Physical Properties of TassieiteHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
Dark green
Streak:
Light green
Comment:
Could not be measured
Tenacity:
Brittle
Cleavage:
Perfect
good to perfect on {100}; a second intersects this at an angle of 60°
Density:
3.45 g/cm3 (Calculated)
Comment:
Could not be measured

Optical Data of TassieiteHide

Type:
Biaxial (+)
RI values:
nα = 1.712(2) nβ = 1.713(2) nγ = 1.722(2)
2V:
Measured: 46° (1), Calculated: 37°
Max. Birefringence:
δ = 0.010
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
Dispersion:
very weak
Pleochroism:
Visible
Comments:
X dark blue, Y blue, Z light brown
Absorption: X > Y >> Z

Chemistry of TassieiteHide

Mindat Formula:
(Na,◻)Ca2(Mg,Fe2+,Fe3+)2(Fe2+,Mg)2(Fe3+,Mg)2(PO4)6 · 2H2O
Element Weights:
Element% weight
O42.404 %
Fe22.771 %
P18.944 %
Ca8.171 %
Mg4.955 %
Na2.344 %
H0.411 %

Calculated from ideal end-member formula.
Elements listed:
Ca, Fe, H, Mg, Na, O, P - search for minerals with similar chemistry

Crystallography of TassieiteHide

Crystal System:
Orthorhombic
Class (H-M):
mmm (2/m 2/m 2/m) - Dipyramidal
Space Group:
Pbca
Setting:
Pbca
Cell Parameters:
a = 12.4595(7) Å, b = 11.5955(16) Å, c = 12.7504(7) Å
Ratio:
a:b:c = 1.075 : 1 : 1.1
Unit Cell V:
1842.1 ų
Z:
4

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0006138TassieiteGrew E S, Armbruster T, Medenbach O, Yates M G, Carson C J (2007) Tassieite, (Na,_)Ca2(Mg,Fe2+,Fe3+)2(Fe3+,Mg)2(Fe2+,Mg)2(PO4)6*2H2O, a new hydrothermal wicksite-group mineral in fluorapatite nodules from granulite- facies paragneiss in the Larsemann Hills, Prydz Bay, East Antarctica The Canadian Mineralogist 45 293-3052007Larsemann Hills, Prydz Bay, East Antarctica0293
0006137TassieiteGrew E S, Armbruster T, Medenbach O, Yates M G, Carson C J (2007) Tassieite, (Na,_)Ca2(Mg,Fe2+,Fe3+)2(Fe3+,Mg)2(Fe2+,Mg)2(PO4)6*2H2O, a new hydrothermal wicksite-group mineral in fluorapatite nodules from granulite- facies paragneiss in the Larsemann Hills, Prydz Bay, East Antarctica The Canadian Mineralogist 45 293-3052007Larsemann Hills, Prydz Bay, East Antarctica0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 4b: Highly evolved igneous rocks>3.0
34 : Complex granite pegmatites

Type Occurrence of TassieiteHide

Type Locality:
ⓘ Johnston Firth, Stornes Peninsula, Larsemann Hills, Prydz Bay, Ingrid Christensen Coast, Princess Elizabeth Land, East Antarctica, Antarctica
General Appearance of Type Material:
A few larger grains of tassieite (i.e., 0.5–1 mm) show crystal faces and cleavage traces, but most grains, which are 0.02 to 0.3 mm in longest dimension, are platy and anhedral
Place of Conservation of Type Material:
Holotype material (sample no. 113002A) is deposited in the National Museum of Natural History (Smithsonian Institution) as catalogue number NMNH 174436, the same as the holotype specimen for stornesite-(Y).
Geological Setting of Type Material:
occurs in a single, rounded nodule ~8–10 cm across of dark brown fluorapatite in biotite – quartz – plagioclase paragneiss
Associated Minerals at Type Locality:
MélonjosephiteMonazite-(Ce)Pyrite'Stornesite-(Y)'Wagnerite
Xenotime-(Y)
Reference:
Grew, E. S., Armbruster, T., Medenbach, O., Yates, M. G., Carson, C. J. (2007) Tassieite, (Na,◻)Ca2(Mg,Fe2+,Fe3+)2(Fe3+,Mg)2(Fe2+,Mg)2(PO4)6 · 2H2O, a new hydrothermal wicksite-group mineral in fluorapatite nodules from granulite-facies paragneiss in the Larsemann Hills, Prydz Bay, East Antarctica. The Canadian Mineralogist, 45 (2) 293-305 doi:10.2113/gscanmin.45.2.293

Synonyms of TassieiteHide

Other Language Names for TassieiteHide

Dutch:Tassieiet
German:Tassieit
Simplified Chinese:镁魏磷石

Relationship of Tassieite to other SpeciesHide

Member of:
Wicksite Group
Other Members of Wicksite Group:
BederiteCa2(Mn2+)4(Fe3+)2(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m)
GrischuniteNaCa2Mn2+5Fe3+(AsO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m)
LiraiteNaCa2Mn2+2[Fe3+Fe2+]Mn2+2(PO4)6(H2O)2Orth. mm2
Maneckiite(Na◻)Ca2Fe2+2(Fe3+Mg)Mn2(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m) : Pbca
WicksiteNaCa2(Fe2+,Mn2+)4MgFe3+(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m) : Pbca

Related Minerals - Strunz-mindat GroupingHide

8.CF.FerraioloiteMgMn2+4(Fe2+0.5Al3+0.5)4Zn4(PO4)8(OH)4(H2O)20Mon.
8.CF.NaalasiteNaAl(AsO3OH)2 · H2OTrig. 3 2 : R3 2
8.CF.NafeasiteNa3Fe3+3(AsO3OH)6 · 3H2OMon. 2 : B2
8.CF.FalsteriteCa2MgMn2+2Fe2+2Fe3+2Zn4(PO4)8(OH)4(H2O)14Mon. 2/m : P21/b
8.CF.EspadaiteNa4Ca3Mg2[AsO3(OH)]2[AsO2(OH)2]10 · 7H2OOrth. mmm (2/m 2/m 2/m) : Ccca
8.CF.LiraiteNaCa2Mn2+2[Fe3+Fe2+]Mn2+2(PO4)6(H2O)2Orth. mm2
8.CF.05BederiteCa2(Mn2+)4(Fe3+)2(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m)
8.CF.05WicksiteNaCa2(Fe2+,Mn2+)4MgFe3+(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.CF.05GrischuniteNaCa2Mn2+5Fe3+(AsO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m)
8.CF.05Maneckiite(Na◻)Ca2Fe2+2(Fe3+Mg)Mn2(PO4)6 · 2H2OOrth. mmm (2/m 2/m 2/m) : Pbca
8.CF.10HaigerachiteKFe3+3(PO3OH)2[PO2(OH)2]6 · 4H2OMon. 2/m : B2/b
8.CF.10YazganiteNaFe3+2(Mg,Mn2+)(AsO4)3 · H2OMon. 2/m : B2/b
8.CF.15CurrieriteNa4Ca3MgAl4(AsO3OH)12 · 9H2OHex. 6 2 2 : P6 2 2
8.CF.20RíosecoiteCa2Mg(AsO3OH)3(H2O)2Tric. 1 : P1

Fluorescence of TassieiteHide

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 TassieiteHide

References for TassieiteHide

Localities for TassieiteHide

Showing 1 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.
Antarctica (TL)
 
  • East Antarctica
    • Princess Elizabeth Land
      • Ingrid Christensen Coast
        • Prydz Bay
          • Larsemann Hills
            • Stornes Peninsula
Grew et al. (2006) +1 other reference
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