Mineralogy Database

Armangite Mineral Data

Search Webmineral :

General Armangite Information

Help on Chemical  Formula: Chemical Formula: Mn26As+++18O50(OH)4(CO3)
Help on Composition: Composition: Molecular Weight = 3,704.99 gm
   Manganese  38.55 %  Mn   49.78 % MnO
   Arsenic    36.40 %  As   48.06 % As2O3
   Hydrogen    0.11 %  H     0.97 % H2O
   Carbon      0.32 %  C     1.19 % CO2
   Oxygen     24.61 %  O
             ______        ______ 
             100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Mn2+26As18O50(OH)4(CO3)
Help on Environment: Environment: On a museum specimen collected from a metamorphosed Fe-Mn deposit.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1920
Help on Locality: Locality: Langban, V´┐Żarmland, Sweden. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Arsenic and MANGanese in the composition.
Help on Name Pronunciation: Name Pronunciation: Armangite + Pronunciation Say ARMANGITE
Help on Synonym: Synonym: ICSD 100555
  PDF 19-780

Armangite Image

Click Here for Larger   Image in a New Browser Window Images:
Click Here for Larger   Image


Comments: Black crystals of armangite on matrix.
Location: Langban, Varmland, Sweden.. Scale: Specimen Size 2.5 x 4 cm.
© John Veevaert

Armangite Crystallography

Help on Axial Ratios: Axial Ratios: a:c = 1:0.65636
Help on Cell Dimensions: Cell Dimensions: a = 13.491, c = 8.855, Z = 1; V = 1,395.75 Den(Calc)= 4.41
Help on Crystal System: Crystal System: Trigonal - Rhombohedral H-M Symbol ( 3) Space Group: P 3
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.774(1), 2.952(0.55), 2.924(0.38),
Help on Forms: Forms:

Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize

S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu

Help on Above

Forms: ( 1 1 0) ( 2 2 1) ( 0 0 1)

Warning: this java applet does not work in some browsers because of security restrictions.


Physical Properties of Armangite

Help on Cleavage: Cleavage: {0001} Good
Help on Color: Color: Black.
Help on Density: Density: 4.43
Help on Diaphaneity: Diaphaneity: Transparent to Opaque
Help on Hardness: Hardness: 4 - Fluorite
Help on Streak: Streak: brown

Optical Properties of Armangite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.041 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.046 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2268,KPDmeas= 0.2257,KC= 0.2168
Ncalc = 1.96
Help on Optical Data: Optical Data: Uniaxial (-), e=1.99, w=2.01, bire=0.0200.

Calculated Properties of Armangite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=4.09 gm/cc
note: Specific Gravity of Armangite =4.43 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0001539734
Boson Index = 0.9998460266
Help on Photoelectric: Photoelectric: PEArmangite = 35.79 barns/electron
U=PEArmangite x rElectron Density= 146.37 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Armangite is Not Radioactive

Armangite Classification

Help on  Dana Class: Dana Class: (46)Basic or Halogen-Containing Antimonites, Arsenites and Phosphites
  (46.02)with miscellaneous formulae
  (46.02.07)Dana Group Armangite Mn26As18O50(OH)4(CO3) P 3 3
Help on  Strunz Class: Strunz Class: 04.JB.20 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate
  04.J - Arsenites, Antimonites, Bismuthites, Sulfites,
  04.JB -Arsenites, antimonites, bismuthites; with additional anions, without H2O
04.JB.20 Armangite Mn26As18O50(OH)4(CO3) P 3 3

Other Armangite Information

Help on References: References: NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Armangite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

Search for Armangite using:

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

Visit our Advertisers for Armangite :

Ask about Armangite 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 Espa˝ol

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


Dana No: Strunz No: 04.JB.20





Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.