Argyrodite Mineral Data

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General Argyrodite Information

Chemical Formula:

Ag8GeS6

Composition:

Molecular Weight = 1,127.95 gm

Silver 76.51 % Ag

Germanium 6.44 % Ge

Sulfur 17.06 % S

______

100.00 %

Empirical Formula:

Ag₈GeS₆

Environment:

In low-temperature polymetallic deposits with silver sulfosalts (Freiberg, Germany); in high-temperature Sn-Ag deposits (Bolivia).

IMA Status:

Valid Species (Pre-IMA) 1886

Locality:

From the Himmelsfurst and other mines, Erbisdorf, near Freiberg, Saxony, Germany. In the Fournial mine, Massiac region, Cantal, France. Link to MinDat.org Location Data.

Name Origin:

For the Greek for "silver-containing."

Name Pronunciation:

Argyrodite + Pronunciation

Argyrodite Image

Images:

Argyrodite

Comments: Lead gray metallic aggregate of argyrodite crystals.
Location: Veta Galufa, Colquechaca, Potosi Dept., Bolivia. Scale: Size Not Given.
© Lou Perloff / Photo Atlas of Minerals

Images:

Argyrodite

Comments: Gray, metallic, massive, crystalline argyrodite ore.
Location: Himmelsfürst mine, Brand-Erbisdorf bei Freiberg, Erzgebirge, Sachsen. Scale: Picture size 4 mm.
© Thomas Witzke / Abraxas-Verlag

Argyrodite Crystallography

Axial Ratios:

a:b:c =2.0263:1:1.4163

Cell Dimensions:

a = 15.149, b = 7.476, c = 10.589, Z = 4; V = 1,199.25 Den(Calc)= 6.25

Crystal System:

Orthorhombic - PyramidalH-M Symbol (mm2) Space Group: Pna2

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

By Intensity(I/I_o): 3.05(1), 2.7(0.6), 3.08(0.4),

Forms:

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

Warning: this large pop-up is very compute intensive and may not work well with some computers.

Crystal Structure:

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Eulenberger G , Monatshefte fur Chemie , 108 (1977) p.901-913, Die kristallstrukture der tieftemperaturmodifikation von Ag8GeS6, Locality: synthetic, Note: z-coordinate of Ag6 altered to reproduce reported bond lengths

Physical Properties of Argyrodite

Cleavage:

None

Color:

Black, Steel gray.

Density:

6.1 - 6.3, Average = 6.19

Diaphaneity:

Opaque

Fracture:

Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.

Habit:

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

Habit:

Subhedral Crystals - Occurs as crystals which tend to exhibit a recognizable crystal shape.

Hardness:

2.5 - Finger Nail

Luster:

Metallic

Streak:

grayish black

Optical Properties of Argyrodite

RL Anisotrophism:

Weak.

RL Color:

Gray-white with a violet tint.

RL Pleochroism:

Very weak.

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Argyrodite in Air**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
400 nm	27.40	29.30
420 nm	26.00	27.60
440 nm	25.20	26.60
460 nm	24.50	25.90
470 nm	24.20	25.60
480 nm	24.00	25.20
500 nm	23.70	24.80
520 nm	23.50	24.50
540 nm	23.30	24.30
546 nm	23.30	24.20
560 nm	23.30	24.20
580 nm	23.20	24.20
589 nm	23.20	24.10
600 nm	23.10	24.00
620 nm	23.10	24.00
640 nm	23.10	23.90
650 nm	23.20	24.00
660 nm	23.20	24.00
680 nm	23.20	24.00
700 nm	23.20	24.10

**Standardized Intensity (100%) Reflection Spectra of Argyrodite in Oil**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
400 nm	11.10	12.00
420 nm	10.70	11.60
440 nm	10.30	11.00
460 nm	9.90	10.60
470 nm	9.80	10.50
480 nm	9.70	10.40
500 nm	9.70	10.30
520 nm	9.60	10.20
540 nm	9.50	10.00
546 nm	9.40	10.00
560 nm	9.40	10.00
580 nm	9.40	10.00
589 nm	9.40	10.00
600 nm	9.50	10.00
620 nm	9.50	10.00
640 nm	9.50	10.00
650 nm	9.50	10.00
660 nm	9.60	10.10
680 nm	9.60	10.10
700 nm	9.70	10.20

**Calculated Relative Intensity Colors of Argyrodite in Air**
Relative Intensity	0%	40%	80%	100%	120%	160%	200%	240%	280%	320%	360%	380%
R₁
R₂

**Calculated Relative Intensity Colors of Argyrodite in Oil**
Relative Intensity	0%	100%	200%	300%	400%	500%	600%	700%	800%	900%	920%
R₁
R₂

Calculated Properties of Argyrodite

Electron Density:

Bulk Density (Electron Density)=5.59 gm/cc
note: Specific Gravity of Argyrodite =6.25 gm/cc.

Fermion Index:

Fermion Index = 0.0063004033
Boson Index = 0.9936995967

Photoelectric:

PE_Argyrodite= 200.29 barns/electron
U=PE_Argyrodite x rElectron Density=1,118.67 barns/cc.

Radioactivity:

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

Argyrodite Classification

Dana Class:

02.05.06.01 (02)Sulfides - Including Selenides and Tellurides

(02.05)where Am Bn Xp, with (m+n):p=3:2

(02.05.06)Argyrodite Group

02.05.06.01 Argyrodite Ag8GeS6 Pna2 mm2

02.05.06.02 Canfieldite Ag8SnS6 P na2₁ mm2

Strunz Class:

02.BA.35 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.35 Argyrodite Ag8GeS6 Pna2 mm2

02.BA.35 Canfieldite Ag8SnS6 P na2₁ mm2

02.BA.35 Putzite! (Cu4.7Ag3.3)GeS6 F43m 4 3m

Other Argyrodite Information

References:

NAME( AntBidBlaNic1) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(CanMin, 42:1762)

See Also:

Links to other databases for Argyrodite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - EUROmin Project
5 - Ecole des Mines de Paris
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - MinMax(Deutsch)
12 - MinMax(English)
13 - Mineralienatlas (Deutsch)
14 - QUT Mineral Atlas
15 - Ruff.Info
16 - WWW-MINCRYST

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

Argyrodite

Ag8GeS6
Dana No: 02.05.06.01 Strunz No: 02.BA.35
Locality:

Notes: