Actinolite Mineral Data

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General Actinolite Information

Chemical Formula:

Ca2(Mg,Fe++)5Si8O22(OH)2

Composition:

Molecular Weight = 853.16 gm

Sodium 0.59 % Na 0.80 % Na₂O

Calcium 8.60 % Ca 12.03 % CaO

Magnesium 9.71 % Mg 16.11 % MgO

Titanium 0.11 % Ti 0.19 % TiO₂

Manganese 0.13 % Mn 0.17 % MnO

Aluminum 1.39 % Al 2.63 % Al₂O₃

Iron 8.58 % Fe 10.61 % FeO / 0.47 % Fe₂O₃

Silicon 25.64 % Si 54.86 % SiO₂

Hydrogen 0.24 % H 2.11 % H₂O

Oxygen 45.01 % O

______ ______

100.00 % 99.97 % = TOTAL OXIDE

Empirical Formula:

Ca_1.83Na_0.22Mg_3.41Fe²⁺_1.26Al_0.23Fe³⁺_0.05Mn²⁺_0.02Ti_0.02Si_7.79Al_0.21O₂₂(OH)₂

Environment:

Metamorphic rocks.

IMA Status:

Valid Species (Pre-IMA) 1794

Locality:

Common world wide. Link to MinDat.org Location Data.

Name Origin:

From the Greek, aktinos, meaning "ray" in allusion to actinolite's fibrous nature.

Name Pronunciation:

Actinolite + Pronunciation

Synonym:

Byssolite

Hexagonite (Mn)

ICSD 24900

Mountain Leather

Nephrite Jade

PDF 41-1366

Smaragdite - emerald green

Actinolite Image

Images:

Actinolite

Comments: Sharp, floater actinolite crystal with a slight green tint.
Location: Namibian dessert, more or less due West of Uis, Namibia. Scale: 8.5 x 2.5 x 2 cm.
© Fabre Minerals

Actinolite Crystallography

Axial Ratios:

a:b:c =0.5436:1:0.2917

Cell Dimensions:

a = 9.84, b = 18.1, c = 5.28, Z = 2; beta = 104.7° V = 909.61 Den(Calc)= 3.11

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: C 2/m

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 8.38(1), 3.12(1), 2.71(0.9),

Crystal Structure:

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Evans B W , Yang H , American Mineralogist , 83 (1998) p.458-475, Fe-Mg order-disorder in tremolite-actinolite-ferro-actinolite at ambient, and high temperature, Sample: NMNH 93728 from Greiner, Zillertal, Austria in act-talc rock

View Additional jPOWD Structure files for Actinolite
[1] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [2] [3] [4] [5] [6] [7] [8] [9]

Physical Properties of Actinolite

Cleavage:

{110} Perfect, {110} Perfect

Color:

Green, Green black, Gray green, Black.

Density:

2.98 - 3.1, Average = 3.04

Diaphaneity:

Translucent to transparent

Fracture:

Splintery - Thin, elongated fractures produced by intersecting good cleavages or partings (e.g. hornblende).

Habit:

Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).

Habit:

Fibrous - Crystals made up of fibers.

Habit:

Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)

Hardness:

5.5 - Knife Blade

Luminescence:

Non-fluorescent.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Actinolite

Gladstone-Dale:

CI meas= -0.002 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.021 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2039,KPDmeas= 0.2086,KC= 0.2082
Ncalc = 1.62 - 1.65

Optical Data:

Biaxial (-), a=1.613-1.628, b=1.627-1.644, g=1.638-1.655, bire=0.0250-0.0270, 2V(Calc)=78-82, 2V(Meas)=84-73. Dispersion r < v.

Pleochroism (x):

very pale yellow, colorless, pale brown, or light green.

Pleochroism (y):

greenish yellow, pale yellow green, pale brown, or bluish green.

Pleochroism (z):

pale green, green, dark green, or pale bluish green.

Calculated Properties of Actinolite

Electron Density:

Bulk Density (Electron Density)=3.02 gm/cc
note: Specific Gravity of Actinolite =3.04 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Actinolite= 4.88 barns/electron
U=PE_Actinolite x rElectron Density= 14.73 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Actinolite is Not Radioactive

Actinolite Classification

Dana Class:

66.01.03a.02 (66)Inosilicate Double-Width Unbranched Chains, W=2

(66.01)with P=2 amphibole configuration

(66.01.03a)Group 2, the calcic amphiboles

66.01.03a.01 Tremolite []Ca2Mg5Si8O22(OH)2 C 2/m 2/m

66.01.03a.02 Actinolite Ca2(Mg,Fe)5Si8O22(OH)2 C 2/m 2/m

66.01.03a.03 Ferro-actinolite []Ca2Fe5Si8O22(OH)2 C 2/m 2/m

66.01.03a.04 Magnesiohornblende Ca2[Mg4(Al,Fe)]Si7AlO22(OH)2 C 2/m 2/m

66.01.03a.05 Ferrohornblende []Ca2[Fe4(Al,Fe)]Si7AlO22(OH)2 C 2/m 2/m

66.01.03a.06 Tschermakite []Ca2(Mg3AlFe)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.06a Aluminoferrotschermakite! []Ca2(Fe2)3Al2(Si6Al2)O22(OH)2 C 2/m 2/m

66.01.03a.06b Ferri-ferrotschermakite! []Ca2(Fe2)3(Fe3)2(Si6Al2)O22(OH)2 C 2/m 2/m

66.01.03a.06c Ferrotschermakite! []Ca2(Fe3AlFe)Si6Al2O22(OH) C 2/m 2/m

66.01.03a.07 Ferro-aluminotschermakite* Ca2Fe3Al2(Si7Al)O22(OH)2 C 2/m 2/m

66.01.03a.08 Ferritschermakite Ca2(Fe,Mg)3Al2(Si7Al)O22(OH)2 C 2/m 2/m

66.01.03a.09 Ferroferritschermakite* Ca2(Fe,Mg)3Fe2(Si7Al)O22(OH)2 C 2/m 2/m

66.01.03a.10 Edenite NaCa2Mg5Si7AlO22(OH)2 C 2/m 2/m

66.01.03a.10a Fluoro-edenite! NaCa2Mg5Si7AlO22(F,OH)2 C 2/m 2/m

66.01.03a.11 Ferro-edenite NaCa2Fe5Si7AlO22(OH)2 C 2/m 2/m

66.01.03a.12 Pargasite NaCa2(Mg,Fe)4Al(Si6Al2)O22(OH)2 C 2/m 2/m

66.01.03a.12a Potassicpargasite! (K,Na)Ca2(Mg,Fe)5Si8O22(OH,F)2 C 2/m 2/m

66.01.03a.13 Ferropargasite NaCa2(Fe4Al)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.13a Ferrochloropargasite! NaCa2(Fe4Al)Si6Al2O22Cl2 C 2/m 2/m

66.01.03a.13b Potassic-chloropargasite! (K,Na)Ca2(Mg,Fe2)4Al(Si6Al2O22)(Cl,OH)2 C 2/m 2/m

66.01.03a.13c Potassic-ferropargasite KCa2(Fe4Al)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.14 Magnesiohastingsite NaCa2(Mg4Fe)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.15 Hastingsite NaCa2(Fe4Fe)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.15a Potassic-chlorohastingsite! (K,Na)Ca2(Fe,Mg)4Fe[Si6Al2O22](Cl,OH)2 C 2/m 2/m

66.01.03a.15b Fluoro-magnesiohastingsite! (Na,K)Ca2(Mg,Fe,Ti)5(Si,Al)8O22F2 C 2/m 2/m

66.01.03a.15c Potassic-magnesiohastingsite! (K,Na)Ca2(Mg,Fe,Fe,Al)5(Si,Al)8O22(OH,Cl)2 C 2/m 2/m

66.01.03a.15d Chloro-potassichastingsite! KCa2(Fe3MgFe)(Si6Al2)S8O22Cl2 C 2/m 2/m

66.01.03a.15e Fluoro-potassichastingsite! KCa2(Fe2,Mg2,Fe)S5(Si6Al2)8O22F2 C 2/m 2/m

66.01.03a.16 Potassic-magnesiosadanagaite (K,Na)Ca2(Mg,Fe,Al,Ti)5[(Si,Al)8O22](OH)2 C 2,Cm,C 2/m Mono

66.01.03a.17 Sadanagaite (K,Na)Ca2(Fe,Mg,Al,Ti)5[(Si,Al)8O22](OH)2 C 2,Cm,C 2/m Mono

66.01.03a.17a Potassicsadanagaite! (K,Na)Ca2[Fe3(Al,Fe)2][Si5Al3O22](OH)2 C 2,Cm,C 2/m Mono

66.01.03a.17b Potassicferrisadanagaite! (K,Na)Ca2(Fe,Mg)2(Fe,Al)2[Si5Al3O22](OH,F,O)2 C 2/m 2/m

66.01.03a.17c Magnesiosadanagaite! NaCa2[Mg3(Al,Fe)2]Si5AlO22(OH)2 C 2/m 2/m

66.01.03a.18 Kaersutite NaCa2(Mg4Ti)Si6Al2O23(OH)2 C 2/m 2/m

66.01.03a.19 Ferrokaersutite NaCa2(Fe4Ti)Si6Al2O22(OH)2 C 2/m 2/m

66.01.03a.20 Fluorocannilloite! CaCa2(Mg4Al)Si5Al3O22F2 C 2/m 2/m

66.01.03a.20a Cannilloite! CaCa2Mg4Al(Si5Al3)O22(OH)2 C 2/m 2/m

Strunz Class:

09.DE.10 09 - SILICATES (Germanates)

09.D - Inosilicates* Structural terminology according to Liebau (1985)

09.DE -Inosilicates with 2-periodic double chains, Si4O11; amphibole family

09.DE.10 Ferritschermakite Ca2(Fe,Mg)3Al2(Si7Al)O22(OH)2 C 2/m 2/m

09.DE.10 Ferro-actinolite []Ca2Fe5Si8O22(OH)2 C 2/m 2/m

09.DE.10 Aluminoferrotschermakite! []Ca2(Fe2)3Al2(Si6Al2)O22(OH)2 C 2/m 2/m

09.DE.10 Edenite NaCa2Mg5Si7AlO22(OH)2 C 2/m 2/m

09.DE.10 Ferri-ferrotschermakite! []Ca2(Fe2)3(Fe3)2(Si6Al2)O22(OH)2 C 2/m 2/m

09.DE.10 Actinolite Ca2(Mg,Fe)5Si8O22(OH)2 C 2/m 2/m

09.DE.10 Cannilloite! CaCa2Mg4Al(Si5Al3)O22(OH)2 C 2/m 2/m

09.DE.10 Fluorocannilloite! CaCa2(Mg4Al)Si5Al3O22F2 C 2/m 2/m

09.DE.10 Ferrohornblende []Ca2[Fe4(Al,Fe)]Si7AlO22(OH)2 C 2/m 2/m

09.DE.10 Ferrokaersutite NaCa2(Fe4Ti)Si6Al2O22(OH)2 C 2/m 2/m

09.DE.10 Ferro-edenite NaCa2Fe5Si7AlO22(OH)2 C 2/m 2/m

09.DE.10 Ferro-aluminotschermakite* Ca2Fe3Al2(Si7Al)O22(OH)2 C 2/m 2/m

09.DE.10 Potassic-magnesiosadanagaite (K,Na)Ca2(Mg,Fe,Al,Ti)5[(Si,Al)8O22](OH)2 C 2,Cm,C 2/m Mono

09.DE.10 Fluoro-edenite! NaCa2Mg5Si7AlO22(F,OH)2 C 2/m 2/m

09.DE.10 Hastingsite NaCa2(Fe4Fe)Si6Al2O22(OH)2 C 2/m 2/m

09.DE.10 Ferrotschermakite! []Ca2(Fe3AlFe)Si6Al2O22(OH) C 2/m 2/m

09.DE.10 Ferroferritschermakite* Ca2(Fe,Mg)3Fe2(Si7Al)O22(OH)2 C 2/m 2/m

09.DE.10 Ferropargasite NaCa2(Fe4Al)Si6Al2O22(OH)2 C 2/m 2/m

09.DE.10 Joesmithite PbCa2(Mg,Fe,Fe)5Si6Be2O22(OH)2 P 2/a 2/m

09.DE.10 Kaersutite NaCa2(Mg4Ti)Si6Al2O23(OH)2 C 2/m 2/m

09.DE.10 Magnesiohastingsite NaCa2(Mg4Fe)Si6Al2O22(OH)2 C 2/m 2/m

09.DE.10 Magnesiohornblende Ca2[Mg4(Al,Fe)]Si7AlO22(OH)2 C 2/m 2/m

09.DE.10 Pargasite NaCa2(Mg,Fe)4Al(Si6Al2)O22(OH)2 C 2/m 2/m

09.DE.10 Potassicsadanagaite! (K,Na)Ca2[Fe3(Al,Fe)2][Si5Al3O22](OH)2 C 2,Cm,C 2/m Mono

09.DE.10 Potassicpargasite! (K,Na)Ca2(Mg,Fe)5Si8O22(OH,F)2 C 2/m 2/m

09.DE.10 Sadanagaite (K,Na)Ca2(Fe,Mg,Al,Ti)5[(Si,Al)8O22](OH)2 C 2,Cm,C 2/m Mono

09.DE.10 Tschermakite []Ca2(Mg3AlFe)Si6Al2O22(OH)2 C 2/m 2/m

09.DE.10 Tremolite []Ca2Mg5Si8O22(OH)2 C 2/m 2/m

09.DE.10 Fluoro-magnesiohastingsite! (Na,K)Ca2(Mg,Fe,Ti)5(Si,Al)8O22F2 C 2/m 2/m

09.DE.10 Parvo-manganotremolite! [](CaMn)2Mg5(Si7Al)O22(OH)2 C 2/m 2/m

09.DE.10 Fluoropargasite! NaCa2(Mg3FeAl)5(Si6Al2O22)F2 C 2/m 2/m

09.DE.10 Parvo-mangano-edenite! Na(CaMn)2Mg5(Si7Al)O22(OH)2 C 2/m 2/m

09.DE.10 Magnesiosadanagaite! NaCa2[Mg3(Al,Fe)2]Si5AlO22(OH)2 C 2/m 2/m

09.DE.10 Fluoro-potassichastingsite! KCa2(Fe2,Mg2,Fe)S5(Si6Al2)8O22F2 C 2/m 2/m

09.DE.10 Chloro-potassichastingsite! KCa2(Fe3MgFe)(Si6Al2)S8O22Cl2 C 2/m 2/m

09.DE.10 Potassic-magnesiohastingsite! (K,Na)Ca2(Mg,Fe,Fe,Al)5(Si,Al)8O22(OH,Cl)2 C 2/m 2/m

09.DE.10 Potassic-ferropargasite KCa2(Fe4Al)Si6Al2O22(OH)2 C 2/m 2/m

Other Actinolite Information

References:

NAME( Sinkankas66) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Heinrich65)

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Print or Cut-and-Paste your Actinolite Specimen Label here :

Actinolite

Ca2(Mg,Fe++)5Si8O22(OH)2
Dana No: 66.01.03a.02 Strunz No: 09.DE.10
Locality:

Notes: