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Actinolite-Ferro-actinolite Series

A solid-solution series between two end-member minerals
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About Actinolite-Ferro-actinolite SeriesHide

Crystal System:
Monoclinic
Series Formula:
◻Ca2(Mg4.5-2.5Fe0.5-2.5)Si8O22(OH)2 to ◻Ca2Fe52+(Si8O22)(OH)2
A series between Actinolite and Ferro-actinolite

Tremolite is defined as having an Mg/ (Mg+Fe2+) ratio ≥ 0.9; actinolite has a ratio of 0.5–0.9 and ferro-actinolite has a ratio of less than 0.5.
See also Actinolite-Tremolite Series.


Unique IdentifiersHide

Mindat ID:
8646
Long-form identifier:
mindat:1:1:8646:8

Age distributionHide

Recorded ages:
Paleoproterozoic : 2260 ± 42 Ma to 1835 Ma - based on 10 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%:
 12345
SiO256.01 %54.73 %55.41 %55.43 %52.09 %
TiO20.1 %0.04 %0.13 %
Al2O31.94 %2.45 %2.33 %3.33 %1.4 %
Fe2O3
FeO7.3 %11.56 %6.42 %5.67 %21.61 %
MnO0.19 %0.09 %0.49 %
MgO19.04 %16.83 %19.89 %20.57 %9.68 %
CaO10.55 %12.22 %12.47 %11.68 %12.2 %
Na2O1.5 %0.61 %0.50 %1.03 %0.24 %
K2O0.09 %0.02 %0.07 %
F
Cr2O30.15 %0.01 %
Total:96.72 %98.4 %97.02 %98.01 %97.92 %
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
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.

Crystallography of Actinolite-Ferro-actinolite SeriesHide

Crystal System:
Monoclinic

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-Ferro-actinolite SeriesHide

Common AssociatesHide

Associations Based on Photo Data:
8 photos of Actinolite-Ferro-actinolite Series associated with QuartzSiO2
3 photos of Actinolite-Ferro-actinolite Series associated with 'Prase'SiO2
2 photos of Actinolite-Ferro-actinolite Series associated with HematiteFe2O3
2 photos of Actinolite-Ferro-actinolite Series associated with AlbiteNa(AlSi3O8)
2 photos of Actinolite-Ferro-actinolite Series associated with ZirconZr(SiO4)

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-Ferro-actinolite Series in petrologyHide

Internet Links for Actinolite-Ferro-actinolite SeriesHide

References for Actinolite-Ferro-actinolite SeriesHide

Reference List:

Localities for Actinolite-Ferro-actinolite SeriesHide

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