Acanthite Mineral Data

Acanthite Mineral Data
Search Webmineral :
   
Home Crystal jmol jPOWD Chem X Ray Dana Strunz Properties A to Z Images       News Help About



[Newest Minerals] [Mineral Auctions] [Mineral Gallery]
The Mineral Gallery's Exceptional Specimens and Mineral Hall of Fame
Visa, PayPal, and Mastercard are Welcomed


General Acanthite Information

Help on Chemical Formula: Chemical Formula: Ag2S
Help on Composition: Composition: Molecular Weight = 247.80 gm
   Silver  87.06 %  Ag
   Sulfur  12.94 %  S
          ______ 
          100.00 % 
Help on Empirical Formula: Empirical Formula: Ag2S
Help on Environment: Environment: Low-temperature sulfide veins and in zones of secondary enrichment.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1855
Help on Locality: Locality: Freiberg, Schneeberg, Annaberg, Germany. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: From the Greek, akanta, meaning "arrow." After the Latin, argentum, meaning "silver". Argentite is stable above 179 C. Acanthite is stable below 179 deg. C.
Help on Name Pronunciation: Name Pronunciation: Acanthite + Pronunciation Say ACANTHITE
Help on Synonym: Synonym: ICSD 30445
  PDF 14-72
  Silver Glance
 

Acanthite Image

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

Acanthite

Comments: Pseudo cubic acanthite crystals on matrix.
Location: Rayas mine, Guanajuato, Mexico. Scale: Size Not Given.
© Lou Perloff / Photo Atlas of Minerals
Click Here for Larger Acanthite Image in a New Browser Window Images:
Click Here for Larger Acanthite Image

Acanthite   Argentite

Comments: Dark metallic acanthite crystals up to 3 mm. Most of the crystals are a cubic habit, so the acanthite is pseudomorphing the original argentite.
Location: San Juan de Rayas Mine (Rayas Mine), Guanajuato, Mun. de Guanajuato, Guanajuato, Mexico. Scale: 18x12x12 mm.
© John Betts - Fine Minerals

Acanthite Crystallography
Help on Axial Ratios: Axial Ratios: a:b:c =0.6101:1:1.1343
Help on Cell Dimensions: Cell Dimensions: a = 4.229, b = 6.931, c = 7.862, Z = 4; beta = 99.61° V = 227.21 Den(Calc)= 7.24
Help on Crystal System: Crystal System: Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 21/n
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.606(1), 2.44(0.8), 2.383(0.75),
Click Here for Large Acanthite Structure Window 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


Wiegers G A , American Mineralogist , 56 (1971) p.1882-1888, The crystal structure of the low-temperature form of silver selenide

 

Physical Properties of Acanthite

Help on Cleavage: Cleavage: {001} Poor, {110} Poor
Help on Color: Color: Lead gray, Gray, Iron black.
Help on Density: Density: 7.2 - 7.4, Average = 7.3
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Sectile - Curved shavings or scrapings produced by a knife blade, (e.g. graphite).
Help on Habit: Habit: Arborescent - "Tree like" growths of branched systems (e.g. silver).
Help on Habit: Habit: Blocky - Crystal shape tends to be equant (e.g. feldspars).
Help on Habit: Habit: Skeletal - Crystals form crude outlines with missing faces.
Help on Hardness: Hardness: 2-2.5 - Gypsum-Finger Nail
Help on Luminescence: Luminescence: Non-fluorescent.
Help on Luster: Luster: Metallic
Help on Magnetism: Magnetism: Nonmagnetic
Help on Streak: Streak: shining black
 

Optical Properties of Acanthite

Help on RL Anisotrophism: RL Anisotrophism: Weak.
Help on RL Bireflectance: RL Bireflectance: None.
Help on RL Pleochroism: RL Pleochroism: None.
Help on Reflectivity Reflectivity
Standardized Intensity (100%) Reflection Spectra of Acanthite in Air
λ R  ∑ R(λ) 
 420 nm   32.90   
 440 nm   33.00 
 460 nm   33.10 
 480 nm   33.00 
 500 nm   32.70 
 520 nm   32.00 
 540 nm   31.20 
 560 nm   30.50 
 580 nm   29.90 
 600 nm   29.20 
 620 nm   28.70 
 640 nm   28.20 
 660 nm   27.60 
 680 nm   27.00 
 700 nm   26.40 
Calculated Relative Intensity Colors of Acanthite in Air
Relative
Intensity		    0%   40%   80% 100% 120% 160% 200% 240% 280% 310%
R                    
 

Calculated Properties of Acanthite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=6.43 gm/cc
note: Specific Gravity of Acanthite =7.24 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0009705112
Boson Index = 0.9990294888
Help on Photoelectric: Photoelectric: PEAcanthite = 224.26 barns/electron
U=PEAcanthite x rElectron Density=1,441.48 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Acanthite is Not Radioactive
 

Acanthite Classification
Help on Dana Class: Dana Class: 02.04.01.01 (02)Sulfides - Including Selenides and Tellurides
  (02.04)where Am Bn Xp, with (m+n):p=2:1
  (02.04.01)Acanthite Group
 
02.04.01.01 Acanthite Ag2S P 21/n 2/m
 
02.04.01.02 Naumannite Ag2Se P 212121 2 2 2
 
02.04.01.03 Aguilarite Ag4SeS P 212121 2 2 2
Help on Strunz Class: Strunz Class: 02.BA.30a 02 - SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulf
  02.B - Metal Sulfides, M:S > 1:1 (mainly 2:1)
  02.BA -With Cu, Ag, Au
 
02.BA.30a Acanthite Ag2S P 21/n 2/m
 
02.BA.30a Argentite* Ag2S I m3m 4/m 3 2/m
 

Other Acanthite Information
Help on References: References: NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic1)
Help on See Also: See Also: Links to other databases for Acanthite :
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 - Glendale Community College
9 - Google Images
10 - Google Scholar
11 - Handbook of Mineralogy (MinSocAm)
12 - Handbook of Mineralogy (UofA)
13 - HyperPhysics
14 - MinDAT
15 - MinMax(Deutsch)
16 - MinMax(English)
17 - Mineral and Gemstone Kingdom
18 - Mineralienatlas (Deutsch)
19 - QUT Mineral Atlas
20 - Ruff.Info
21 - WWW-MINCRYST

Search for Acanthite using:

Google
 
Web webmineral.com
[ALTAVISTA] [AOL] [All-The-Web] [HotBot] [Ixquick] [MAMMA] [MSN.COM] [Netscape] [Scirus] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Acanthite :

AA Mineral Specimens

B & L Fine Minerals

Crystalarium.com

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

Dakota Matrix

Desert Winds Gems and Minerals

Excalibur Minerals

Exceptional Minerals

Fabre Minerals

Heliodor

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

Wrights Rock Shop

Translate Acanthite Mineral Data :

Ask about Acanthite 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 Espaņol

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

Acanthite

Ag2S
Dana No: 02.04.01.01 Strunz No: 02.BA.30a
Locality:

 

Notes: