Aegirine-augite
A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
About Aegirine-augite
Formula:
(NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
a+b+c+d = 1
e+f+g=h = 1
a = e+f
0.2 ≤ a ≤ 0.8
e > f
e+f+g=h = 1
a = e+f
0.2 ≤ a ≤ 0.8
e > f
Hardness:
6
Crystal System:
Monoclinic
Member of:
Aegirine-augite was mostly treated as a variety until Joan R. Clark and James J. Papike (1968) redefined aegirine-augite from a neotype location, although the validation of aegirine-augite did not materially alter the original description except to restrict the crystal structure. It was formally redefined as part of the IMA's restructuring of the Pyroxene group by Morimoto et al. (1988), see diagram below.
Unique Identifiers
Classification of Aegirine-augite
Accepted names for Na pyroxenes (after Morimoto et al., 1988).
IMA Classification of Aegirine-augite
Approved
IMA status notes:
Redefined by the IMA
IMA Formula:
(Ca,Na)(Fe3+,Mg,Fe2+)Si2O6
Approval history:
Redefined by IMA: 1988 (special procedure).
9.DA.20
9 : SILICATES (Germanates)
D : Inosilicates
A : Inosilicates with 2-periodic single chains, Si2O6; pyroxene family
9 : SILICATES (Germanates)
D : Inosilicates
A : Inosilicates with 2-periodic single chains, Si2O6; pyroxene family
65.1.3b.2
65 : INOSILICATES Single-Width,Unbranched Chains,(W=1)
1 : Single-Width Unbranched Chains, W=1 with chains P=2
65 : INOSILICATES Single-Width,Unbranched Chains,(W=1)
1 : Single-Width Unbranched Chains, W=1 with chains P=2
16.24.1
16 : Silicates Containing Aluminum and other Metals
24 : Aluminosilicates of Fe, Mg, Ca and alkalis
16 : Silicates Containing Aluminum and other Metals
24 : Aluminosilicates of Fe, Mg, Ca and alkalis
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.
Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.
Symbol | Source | Reference |
---|---|---|
Aeg-Aug | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Aeg-Aug | Kretz (1983) | Kretz, R. (1983) Symbols of rock-forming minerals. American Mineralogist, 68, 277–279. |
Aeg-Aug | Siivolam & Schmid (2007) | Siivolam, J. and Schmid, R. (2007) Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: List of mineral abbreviations. Web-version 01.02.07. IUGS Commission on the Systematics in Petrology. download |
Aeg-Aug | Whitney & Evans (2010) | Whitney, D.L. and Evans, B.W. (2010) Abbreviations for names of rock-forming minerals. American Mineralogist, 95, 185–187 doi:10.2138/am.2010.3371 |
Physical Properties of Aegirine-augite
Hardness:
6 on Mohs scale
Optical Data of Aegirine-augite
Type:
Biaxial (-)
RI values:
nα = 1.700 - 1.760 nβ = 1.710 - 1.800 nγ = 1.730 - 1.813
2V:
Measured: 70° to 110°, Calculated: 58° to 72°
Max Birefringence:
δ = 0.030 - 0.053
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:
High
Dispersion:
r > v moderate
Chemistry of Aegirine-augite
Mindat Formula:
(NaaCabFe2+cMgd)(Fe3+eAlfFe2+gMgh)Si2O6
a+b+c+d = 1
e+f+g=h = 1
a = e+f
0.2 ≤ a ≤ 0.8
e > f
a+b+c+d = 1
e+f+g=h = 1
a = e+f
0.2 ≤ a ≤ 0.8
e > f
Chemical Analysis
Oxide wt%:
1 | 2 | 3 | |
---|---|---|---|
SiO2 | 51,10 % | 52.14 % | 52.59 % |
TiO2 | 0.28 % | 0.47 % | 0.23 % |
ZrO2 | 1.30 % | 0.06 % | % |
SnO2 | 0.12 % | % | % |
Al2O3 | 1.02 % | 0.29 % | 0.13 % |
Fe2O3 | 15.77 % | % | % |
FeO | 9.62 % | % | % |
MnO | 1.13 % | 1.36 % | 0.95 % |
MgO | 0.96 % | 4.92 % | 7.10 % |
CaO | 9.72 % | 12.14 % | 14.08 % |
Na2O | 7.66 % | 6.99 % | 5.69 % |
V2O3 | % | 0.66 % | 2.00 % |
Fe2O3* | % | 16.39 % | 12.13 % |
FeO* | % | 4.60 % | 5.02 % |
ZnO | % | 0.06 % | 0.03 % |
SrO | % | 0.05 % | 0.05 % |
NiO | % | % | 0.02 % |
Total: | 98.58 % | 100.13 % | 100.02 % |
Empirical formulas:
Sample ID | Empirical Formula |
---|---|
2 | (Na0.52Ca0.48)(Fe3+0.47Mg0.28Fe2+0.15Mn2+0.04V0.02Ca0.02Ti0.01)[Si1.99Al0.01O6] |
3 | (Ca0.57Na0.42Mn2+0.01)(Mg0.40Fe3+0.35Fe2+0.16V0.06Mn2+0.02Ti0.01)[Si2.00O6] |
Sample references:
ID | Locality | Reference | Notes |
---|---|---|---|
1 | Skutesundskjær, Barkevik area, Larvik, Vestfold, Norway | Contains 68ppm Li | |
2 | North Wilson pit, Union Carbide Mine, Wilson Springs, Garland County, Arkansas, USA | average of 2 analyses of patchy "higher z" zones in abundant aegirine-augite, in wollastonite. Normalized to ∑(cations) = 4. *Fe3+/∑Fe calculated by charge balance. | |
3 | " " | average of 2 analyses of the main "lower z" portions of abundant aegirine-augite, in wollastonite. Normalized to ∑(cations) = 4. *Fe3+/∑Fe calculated by charge balance. |
Crystallography of Aegirine-augite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/b
Setting:
C2/c
Cell Parameters:
a = 9.663(3) Å, b = 8.813(3) Å, c = 5.2184(16) Å
β = 106.40(2)°
β = 106.40(2)°
Ratio:
a:b:c = 1.096 : 1 : 0.592
Unit Cell V:
426.32 ų (Calculated from Unit Cell)
Z:
4
Comment:
Cell data from Mills & Groat (2008).
Geological Environment
Paragenetic Mode(s):
Paragenetic Mode | Earliest Age (Ga) |
---|---|
Stage 3a: Earth’s earliest Hadean crust | >4.50 |
7 : Ultramafic igneous rocks | |
Stage 4a: Earth’s earliest continental crust | >4.4-3.0 |
19 : Granitic intrusive rocks | |
Near-surface Processes | |
23 : Subaerial aqueous alteration by non-redox-sensitive fluids (see also #47) | |
26 : Hadean detrital minerals | |
Stage 4b: Highly evolved igneous rocks | >3.0 |
35 : Ultra-alkali and agpaitic igneous rocks | |
36 : Carbonatites, kimberlites, and related igneous rocks | |
Stage 5: Initiation of plate tectonics | <3.5-2.5 |
39 : High-𝑃 metamorphism (blueschist, eclogite, ultrahigh 𝑃 facies) | |
40 : Regional metamorphism (greenschist, amphibolite, granulite facies) | |
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere | <0.6 |
51 : Pyrometamorphic minerals (see also #54 and #56) | <0.36 |
Synonyms of Aegirine-augite
Other Language Names for Aegirine-augite
Simplified Chinese:霓辉石
Varieties of Aegirine-augite
Blanfordite | Mn-bearing variety of aegirine-augite. |
Grünblende | A variety of Augite/Aegirin-Augite/Aegirine. Acicular crystals of these pyroxenes covering a quartz xenolith. Literally "green blende". Originally reported from the Eifel, Germany. See also Porricin. |
Porricin | A variety of Augite/Aegirin-Augite/Aegirine. Acicular crystals of these pyroxenes covering a quartz xenolith. Originally reported from the Eifel, Germany. See also Grünblende. |
Urbanite | An Fe-rich augite or aegirine-augite. |
Relationship of Aegirine-augite to other Species
Member of:
Other Members of this group:
Aegirine | NaFe3+Si2O6 | Mon. 2/m : B2/b |
Augite | (CaxMgyFez)(Mgy1Fez1)Si2O6 | Mon. 2/m : B2/b |
Burnettite | CaVAlSiO6 | Mon. 2/m : B2/b |
Clinoenstatite | MgSiO3 | Mon. 2/m : P21/b |
Clinoferrosilite | Fe2+2Si2O6 | Mon. 2/m : P21/b |
Colomeraite | NaTi3+Si2O6 | Mon. 2/m : B2/b |
Davisite | CaScAlSiO6 | Mon. 2/m : B2/b |
Diopside | CaMgSi2O6 | Mon. 2/m : B2/b |
Esseneite | CaFe3+[AlSiO6] | Mon. 2/m : B2/b |
Grossmanite | CaTi3+ AlSiO6 | Mon. 2/m : B2/b |
Hedenbergite | CaFe2+Si2O6 | Mon. 2/m : B2/b |
Jadeite | Na(Al,Fe3+)Si2O6 | Mon. 2/m : B2/b |
Jervisite | NaSc3+Si2O6 | Mon. 2/m : B2/b |
Johannsenite | CaMn2+Si2O6 | Mon. 2/m : B2/b |
Kanoite | Mn2+(Mg,Mn2+)Si2O6 | Mon. 2/m : P21/b |
Kosmochlor | NaCrSi2O6 | Mon. 2/m : B2/b |
Kushiroite | CaAl[AlSiO6] | Mon. 2/m : B2/b |
Namansilite | NaMn3+Si2O6 | Mon. 2/m : B2/b |
Natalyite | NaV3+Si2O6 | Mon. 2/m : B2/b |
Omphacite | (NaaCabFe2+cMgd)(AleFe3+fFe2+gMgh)Si2O6 | Mon. 2/m |
Petedunnite | Ca(Zn,Mn2+,Mg,Fe2+)Si2O6 | Mon. 2/m : B2/b |
Pigeonite | (CaxMgyFez)(Mgy1Fez1)Si2O6 | Mon. 2/m : P21/b |
Ryabchikovite | CuMgSi2O6 | Mon. 2/m : P21/b |
Spodumene | LiAlSi2O6 | Mon. 2/m : B2/b |
Tissintite | (Ca,Na,◻)AlSi2O6 | Mon. 2/m : B2/b |
UM2001-19-SiO:AlCaMgNa | (Na,Mg,Ca)(Mg,Al)Si2O6 | Mon. 2/m : B2/b |
UM2003-36-SiO:CaNa | NaCrSi2O6 - CaMgSi2O6 | Mon. 2/m : B2/b |
Common Associates
Associated Minerals Based on Photo Data:
33 photos of Aegirine-augite associated with Quartz | SiO2 |
20 photos of Aegirine-augite associated with Sanidine | K(AlSi3O8) |
15 photos of Aegirine-augite associated with Nosean | Na8(Al6Si6O24)(SO4) · H2O |
15 photos of Aegirine-augite associated with Nepheline | Na3K(Al4Si4O16) |
11 photos of Aegirine-augite associated with Magnetite | Fe2+Fe3+2O4 |
10 photos of Aegirine-augite associated with Titanite | CaTi(SiO4)O |
10 photos of Aegirine-augite associated with Microcline | K(AlSi3O8) |
9 photos of Aegirine-augite associated with Nosean-phonolite | |
9 photos of Aegirine-augite associated with Calcite | CaCO3 |
7 photos of Aegirine-augite associated with Albite | Na(AlSi3O8) |
Related Minerals - Strunz-mindat Grouping
9.DA. | Protoenstatite | Mg2Si2O6 |
9.DA. | Ryabchikovite | CuMgSi2O6 |
9.DA. | Colomeraite | NaTi3+Si2O6 |
9.DA.05 | Donpeacorite | (Mn,Mg)MgSi2O6 |
9.DA.05 | Enstatite | Mg2Si2O6 |
9.DA.05 | Ferrosilite | Fe2+2Si2O6 |
9.DA.10 | Clinoenstatite | MgSiO3 |
9.DA.10 | Clinoferrosilite | Fe2+2Si2O6 |
9.DA.10 | Kanoite | Mn2+(Mg,Mn2+)Si2O6 |
9.DA.10 | Pigeonite | (CaxMgyFez)(Mgy1Fez1)Si2O6 |
9.DA.15 | Augite | (CaxMgyFez)(Mgy1Fez1)Si2O6 |
9.DA.15 | Diopside | CaMgSi2O6 |
9.DA.15 | Esseneite | CaFe3+[AlSiO6] |
9.DA.15 | Hedenbergite | CaFe2+Si2O6 |
9.DA.15 va | Jeffersonite | Ca(Mn,Zn,Fe)Si2O6 |
9.DA.15 | Johannsenite | CaMn2+Si2O6 |
9.DA.15 | Petedunnite | Ca(Zn,Mn2+,Mg,Fe2+)Si2O6 |
9.DA.15 | Davisite | CaScAlSiO6 |
9.DA.15 | Kushiroite | CaAl[AlSiO6] |
9.DA.15 | Grossmanite | CaTi3+ AlSiO6 |
9.DA.20 | Omphacite | (NaaCabFe2+cMgd)(AleFe3+fFe2+gMgh)Si2O6 |
9.DA.25 | Aegirine | NaFe3+Si2O6 |
9.DA.25 | Jadeite | Na(Al,Fe3+)Si2O6 |
9.DA.25 | Jervisite | NaSc3+Si2O6 |
9.DA.25 | Kosmochlor | NaCrSi2O6 |
9.DA.25 | Namansilite | NaMn3+Si2O6 |
9.DA.25 | Natalyite | NaV3+Si2O6 |
9.DA.25 | Tissintite | (Ca,Na,◻)AlSi2O6 |
9.DA.30 | Spodumene | LiAlSi2O6 |
9.DA.35 | Hiroseite | FeSiO3 |
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Aegirine-augite in petrology
An essential component of rock names highlighted in red, an accessory component in rock names highlighted in green.
Internet Links for Aegirine-augite
mindat.org URL:
https://www.mindat.org/min-32.html
Please feel free to link to this page.
Please feel free to link to this page.
Search Engines:
External Links:
References for Aegirine-augite
Reference List:
Papike, Joan R. Clark arid J. J. (1968) Crystal-chemical characterization of omphacites. American Mineralogist, 53 (5-6) 840-868
Localities for Aegirine-augite
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).
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.
All localities listed without proper references should be considered as questionable.
Quick NavTopAbout Aegirine-augiteUnique IdentifiersClassification IMA Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Chemical AnalysisCrystallography Geological EnvironmentSynonymsOther LanguagesVarietiesRelationshipsCommon AssociatesStrunz-MindatOther InformationAegirine-augite in petrologyInternet Links References Localities Locality List
Laacher See Volcanic Complex, Germany