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Actinolite Root Name Group

A group of related mineral species
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About Actinolite Root Name GroupHide

Formula:
◻Ca2(Mg0-4.5C2+0.5-5)Si8O22(OH,F,Cl)2
C= Fe2+ or Mn2+
W=(OH), F or Cl

On mindat.org we avoid using variables with the same symbol as elements and deviate from the IMA nomenclaure in that we use X rather than B, Z rather than C and (OH,F,Cl,O) rather than W.
The actinolite root name group minerals is defined as monoclinic amphiboles in the calcium amphibole subgroup C(Al+Fe3++2Ti)≤0.5 apfu and Mg<4.5 apfu. The actinolite minerals are defined by the dominant element in the C position and the W position.

There is a solid solution series between all the members in this series.


Unique IdentifiersHide

Mindat ID:
52952
Long-form identifier:
mindat:1:1:52952:9

Chemistry of Actinolite Root Name GroupHide

Mindat Formula:
◻Ca2(Mg0-4.5C2+0.5-5)Si8O22(OH,F,Cl)2

C= Fe2+ or Mn2+
W=(OH), F or Cl

On mindat.org we avoid using variables with the same symbol as elements and deviate from the IMA nomenclaure in that we use X rather than B, Z rather than C and (OH,F,Cl,O) rather than W.

Age distributionHide

Recorded ages:
Paleoproterozoic : 2260 ± 42 Ma to 1835 Ma - based on 11 recorded ages.
Sample ages:
Sample IDRecorded ageGeologic TimeDating method
11853 to 1835 MaOrosirianAr-Ar
21895 to 1877 MaOrosirianAr-Ar
31915 to 1897 MaOrosirianAr-Ar
41943 to 1927 MaOrosirianAr-Ar
52260 ± 42 MaRhyacianK-Ar

Chemical AnalysisHide

Oxide wt%:
 123456
SiO256.01 %54.73 %55.41 %55.43 %52.09 %52.59 %
TiO20.1 %0.04 %0.13 %
Al2O31.94 %2.45 %2.33 %3.33 %1.4 %0.09 %
Fe2O3
FeO7.3 %11.56 %6.42 %5.67 %21.61 %
MnO0.19 %0.09 %0.49 %20.11 %
MgO19.04 %16.83 %19.89 %20.57 %9.68 %8.12 %
CaO10.55 %12.22 %12.47 %11.68 %12.2 %10.92 %
Na2O1.5 %0.61 %0.50 %1.03 %0.24 %0.06 %
K2O0.09 %0.02 %0.07 %0.05 %
F0.30 %
Cr2O30.15 %0.01 %
Fe2O3*0.22 %
FeO*5.96 %
H2O*1.83 %
-O=(F+Cl)-0.13 %
Total:96.72 %98.4 %97.02 %98.01 %97.92 %100.12 %
Empirical formulas:
Sample IDEmpirical Formula
3?(Na0.14Ca1.86)Σ2.00 ( Mg4.13Fe2+0.46Fe3+0.29Al0.11)Σ4.99(Al0.27Si7.73)Σ8.00O22OH2
4Na0.02 (Na0.26Ca1.74)Σ2.00 ( Mg4.25 Mn0.01Fe0.66Cr0.02Al0.22)Σ5.16(Al0.32Si7.68)Σ8.00O22OH2
5(Na0.049K0.013)Σ0.062 (Ca1.961Na0.021Mn0.018)Σ2 (Fe2+2.632Mg2.165Fe3+0.08Al0.063Mn0.045Ti0.015Cr0.001)Σ5.001 (Si7.815Al0.185)Σ8O22 ((OH)1.971O0.029)Σ2
6((K0.010.99)(Ca1.78Mn2+0.21Na0.02)(Mn2+2.38Mg1.84Fe2+0.76Fe3+0.02)[Si7.98Al0.02O22]([OH]1.86F0.14)
Sample references:
IDLocalityReferenceNotes
1Sierra de las Minas, Motagua Valley, GuatemalaSample from late forming vein associated with jadeitite.
2Changpu, Yuexi County, Anqing, Anhui, ChinaSample from the corona around omphacite from a retrograded eclogite
3Kovalo eclogites, Kechros, Arriana, Rhodope, Eastern Macedonia and Thrace, GreeceEMPA analysis from the core of an amphibole from a retrogressed eclogite. The amphibole is from a symplectitic intergrowth with plagioclase after omphacite.
4Steinsteg eclogite, Frosnitz valley, Matrei in Osttirol, Lienz District, Tyrol, AustriaEMPA analysis of an amphibole inclusion in garnet from a post-eclogite facies mica schist.
5Engebøfjellet Eclogite Deposit, Naustdal, Sunnfjord, Vestland, NorwayRetrograde amphibole in late stage veins. Formula normalized by use of Locock, A. J. (2014). An Excel spreadsheet to classify chemical analyses of amphiboles following the IMA 2012 recommendations. Computers & Geosciences, 62, 1-11.
6Gåsborn, Filipstad, Värmland County, SwedenThe original published oxide data from Damman (1989) have been re-normalized to (Si+Al)=8; the oxide values presented here are based on the re-normalization; *Fe measured as Fe2+, with Fe3+ and Fe2O3 derived by charge balance; OH and H2O calculated by stoichiometry.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0002000Ferro-actinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature in an alteration of hornblende, after heating at 700 C American Mineralogist 83 458-47519980293
0001999Ferro-actinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature in an alteration of hornblende American Mineralogist 83 458-47519980293
0001998ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001997ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001996ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001995ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001994ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001993ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001992ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 800 C American Mineralogist 83 458-47519980293
0001991ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001990ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 600 C American Mineralogist 83 458-47519980293
0001989ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001988ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001987ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001986ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001985ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001984ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001983ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
0001982ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature after heating at 700 C American Mineralogist 83 458-47519980293
0001981ActinoliteEvans B W, Yang H (1998) Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient and high temperature American Mineralogist 83 458-47519980293
CIF Raw Data - click here to close

Other Language Names for Actinolite Root Name GroupHide

Relationship of Actinolite Root Name Group to other SpeciesHide

Other Members of Calcium Amphibole Subgroup:
Cannilloite Root Name GroupCaCa2(Z2+4Z3+)(Si5Al3O22)(OH,F,Cl)2
Edenite Root Name GroupACa2Z5(AlSi7O22)((OH),F,Cl)2Mon.
Hastingsite Root Name GroupACa2(Z2+4Fe3+)(Al2Si6O22)(OH,F,Cl)2
Hornblende Root Name Group◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2Mon.
JoesmithitePb2+Ca2(Mg3Fe3+2)(Si6Be2)O22(OH)2Mon. 2/m : P2/b
Pargasite Root Name Group(A)(Ca2){Z2+4Z3+)(Al2Si6O22)(OH,F,Cl)2
Sadanagaite Root Name GroupA (Ca2)(Z2+3Z3+2)(Si5Al3O22)(OH,F,Cl)2Mon.
Tremolite Root Name Group◻Ca2(Mg4.5-5M2+0-0.5)Si8O22W2
Tschermakite Root Name Group◻(Ca2)(Z2+3Z3+2}(Al2Si6O22)(OH,F,Cl)2
Actinolite Root Name Group Members:
Actinolite ◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2Mon. 2/m : B2/m
Ferro-actinolite ◻Ca2Fe2+5(Si8O22)(OH)2Mon. 2/m : B2/m
'Mangano-actinolite' ◻Ca2(Mn,Mg,Fe)5(Si8O22)(OH)2

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.

Actinolite Root Name Group in petrologyHide

Internet Links for Actinolite Root Name GroupHide

References for Actinolite Root Name GroupHide

Localities for Actinolite Root Name GroupHide

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