Magnesiochloritoid Mineral Data

General Magnesiochloritoid Information

Chemical Formula:

MgAl2SiO5(OH)2

Composition:

Molecular Weight = 220.37 gm

Magnesium 11.03 % Mg 18.29 % MgO

Aluminum 24.49 % Al 46.27 % Al₂O₃

Silicon 12.74 % Si 27.27 % SiO₂

Hydrogen 0.91 % H 8.18 % H₂O

Oxygen 50.82 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

MgAl₂SiO₅(OH)₂

Environment:

In metapelites and related rocks within high-grade blueschist rocks; stable under metamorphic conditions of near 500 ±C and 18 kbar.

IMA Status:

Approved IMA 1983

Locality:

Monte Rosa massif, near the Ghiacciaio di Verra; in the Val d'Ayas, Italy, near the border with Switzerland. Link to MinDat.org Location Data.

Name Origin:

Named for magnesium in its composition and its relation to chloritoid.

Synonym:

Sismondine

Search for Magnesiochloritoid Images

Images:

Image not yet available on Webmineral.com

Try searching images.google.com or Mindat Picture Gallary for mineral pictures. Caution: The images retrieved may not be appropriate.

Magnesiochloritoid Crystallography

Axial Ratios:

a:b:c =1.7291:1:3.3233

Cell Dimensions:

a = 9.46, b = 5.471, c = 18.182, Z = 9; beta = 101.4° V = 922.46 Den(Calc)= 3.57

Crystal System:

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

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

By Intensity(I/I_o): 4.47(1), 2.46(0.9), 2.97(0.8),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Ivaldi G , Catti M , Ferraris G , American Mineralogist , 73 (1988) p.358-364, Crystal structure at 25 and 700 C of magnesiochloritoid from a high-pressure, assemblage (Monte Rosa), Sample at 25 C

View Additional jPOWD Structure files for Magnesiochloritoid
[1] [2] [3] [4]

Physical Properties of Magnesiochloritoid

Cleavage:

{001} Perfect, {110} Distinct

Color:

Greenish gray, Greenish black.

Density:

3.5 - 3.6, Average = 3.55

Diaphaneity:

Translucent

Hardness:

6.5 - Pyrite

Luster:

Pearly

Streak:

gray white

Optical Properties of Magnesiochloritoid

Gladstone-Dale:

CI meas= 0.065 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= 0.07 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2017,KPDmeas= 0.2028,KC= 0.2169
Ncalc = 1.76 - 1.78

Optical Data:

Biaxial (?), b=1.72

Calculated Properties of Magnesiochloritoid

Electron Density:

Bulk Density (Electron Density)=3.54 gm/cc
note: Specific Gravity of Magnesiochloritoid =3.55 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_{Magnesiochloritoid}= 1.47 barns/electron
U=PE_{Magnesiochloritoid} x rElectron Density= 5.20 barns/cc.

Radioactivity:

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

Magnesiochloritoid Classification

Dana Class:

52.03.03.02 (52)Nesosilicate Insular SiO4 Groups and O, OH, F, and H2O

(52.03)with cations in [6] coordination only

(52.03.03)Chloritoid group

52.03.03.01 Chloritoid (Fe,Mg,Mn)2Al4Si2O10(OH)4 P1 1

52.03.03.02 Magnesiochloritoid MgAl2SiO5(OH)2 C 2/c 2/m

52.03.03.03 Ottrelite (Mn,Fe,Mg)2Al4Si2O10(OH)4 C 2/c 2/m

52.03.03.04 Carboirite-VIII Fe(Al,Ge)2O[(Ge,Si)O4](OH)2 C1 1

Strunz Class:

09.AF.85 09 - SILICATES (Germanates)

09.A - Nesosilicates

09.AF -Nesosilicates with additional anions;

09.AF.85 Chloritoid (Fe,Mg,Mn)2Al4Si2O10(OH)4 P1 1

09.AF.85 Magnesiochloritoid MgAl2SiO5(OH)2 C 2/c 2/m

09.AF.85 Ottrelite (Mn,Fe,Mg)2Al4Si2O10(OH)4 C 2/c 2/m

Other Magnesiochloritoid Information

References:

NAME( AntBidBlaNic2) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Magnesiochloritoid :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - Handbook of Mineralogy (MinSocAm)
7 - Handbook of Mineralogy (UofA)
8 - MinDAT
9 - Mineralienatlas (Deutsch)
10 - Online Mineral Museum
11 - QUT Mineral Atlas
12 - Ruff.Info
13 - WWW-MINCRYST

Search for Magnesiochloritoid using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Magnesiochloritoid :

A Bijoux Google Search for Magnesiochloritoid
Adam's Minerals Google Search for Magnesiochloritoid
Cape Minerals Google Search for Magnesiochloritoid
Dakota Matrix Minerals Google Search for Magnesiochloritoid
Excalibur Mineral Corp. Google Search for Magnesiochloritoid
Exceptional Minerals Google Search for Magnesiochloritoid
John Betts Fine Minerals Search for Magnesiochloritoid
McDougall Minerals Google Search for Magnesiochloritoid
Mineral News Website Link
Rock and Mineral Shows Google Search for Magnesiochloritoid
Weinrich Minerals, Inc. Google Search for Magnesiochloritoid

Ask about Magnesiochloritoid here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

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

Magnesiochloritoid

MgAl2SiO5(OH)2
Dana No: 52.03.03.02 Strunz No: 09.AF.85
Locality:

Notes: