Magnesiohornblende Mineral Data

General Magnesiohornblende Information

Chemical Formula:

Ca2[Mg4(Al,Fe+++)]Si7AlO22(OH)2

Composition:

Molecular Weight = 821.16 gm

Calcium 9.76 % Ca 13.66 % CaO

Magnesium 11.84 % Mg 19.63 % MgO

Aluminum 5.75 % Al 10.86 % Al₂O₃

Iron 1.70 % Fe 2.43 % Fe₂O₃

Silicon 23.94 % Si 51.22 % SiO₂

Hydrogen 0.25 % H 2.19 % H₂O

Oxygen 46.76 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ca₂Mg₄Al_0.75Fe³⁺_0.25(Si₇AlO₂₂)(OH)₂

Environment:

Igneous and metamorphic rocks.

IMA Status:

Approved IMA 1978

Locality:

Probably common worldwide in "hornblende" granites and shists. Link to MinDat.org Location Data.

Name Origin:

Named for the composition and its relationship to hornblende.

Synonym:

Aluminomagnesiohornblende

Hornblende

ICSD 79834

PDF 45-1371

Magnesiohornblende Image

Images:

Magnesiohornblende

Comments: Dark greenish-black massive magnesiohornblende.
Location: Willi Agatz Mine, Dresden, Saxony, Germany. Scale: Picture size 5.5 cm.
© Thomas Witzke / Abraxas-Verlag

Magnesiohornblende Crystallography

Axial Ratios:

a:b:c =0.544:1:0.292

Cell Dimensions:

a = 9.887, b = 18.174, c = 5.308, Z = 2; beta = 105° V = 921.28 Den(Calc)= 2.96

Crystal System:

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

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

By Intensity(I/I_o): 3.14(1), 8.51(0.55), 2.72(0.35),

Physical Properties of Magnesiohornblende

Cleavage:

{???} Perfect, {???} Distinct

Color:

Brown, Green, Greenish brown, Greenish black, Dark green.

Density:

3 - 3.47, Average = 3.23

Diaphaneity:

Translucent to opaque

Fracture:

Sub Conchoidal - Fractures developed in brittle materials characterized by semi-curving surfaces.

Habit:

Columnar - Forms columns

Habit:

Massive - Fibrous - Distinctly fibrous fine-grained forms.

Habit:

Massive - Granular - Common texture observed in granite and other igneous rock.

Hardness:

5-6 - Between Apatite and Orthoclase

Luminescence:

Non-fluorescent.

Luster:

Vitreous - Pearly

Streak:

white

Optical Properties of Magnesiohornblende

Gladstone-Dale:

CI meas= 0.04 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.049 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2226,KPDmeas= 0.2037,KC= 0.2121
Ncalc = 1.63 - 1.74

Optical Data:

Biaxial (-), a=1.616-1.68, b=1.626-1.695, g=1.636-1.7, bire=0.0200, 2V(Calc)=58-88, 2V(Meas)=66-85. Dispersion r > v or r < v.

Pleochroism (x):

light green, yellowish green, yellow, greenish brown, or yellow.

Pleochroism (y):

dark green, dark yellowish green, brown. Pale, reddish brown, or greenish yellow.

Calculated Properties of Magnesiohornblende

Electron Density:

Bulk Density (Electron Density)=3.22 gm/cc
note: Specific Gravity of Magnesiohornblende =3.24 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_{Magnesiohornblende}= 3.05 barns/electron
U=PE_{Magnesiohornblende} x rElectron Density= 9.83 barns/cc.

Radioactivity:

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

Magnesiohornblende Classification

Dana Class:

66.01.03a.04 (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 Magnesiohornblende Information

See Also:

Links to other databases for Magnesiohornblende :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - Franklin Minerals(Dunn)
8 - GeoScienceWorld
9 - Google Images
10 - Google Scholar
11 - Handbook of Mineralogy (MinSocAm)
12 - Handbook of Mineralogy (UofA)
13 - MinDAT
14 - Mineralienatlas (Deutsch)
15 - Online Mineral Museum
16 - QUT Mineral Atlas
17 - Ruff.Info

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Magnesiohornblende

Ca2[Mg4(Al,Fe+++)]Si7AlO22(OH)2
Dana No: 66.01.03a.04 Strunz No: 09.DE.10
Locality:

Notes:

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