Giraudite Mineral Data

Giraudite Mineral Data +

[Content and History] [Recent Issues] [Back Issues] [Subscriptions] [Contacts]
See Also: [Diamond Crystals] [Excalibur Minerals] [Hudson Institute] [Minerals on CDROM]
Mineral News was founded some twenty years ago and has developed a following of
avid mineral collectors seeking timely information about new finds and other items
of interest to the collector community. Articles are solicited from collector and scientific authors.

General Giraudite Information

Chemical Formula:

(Cu,Zn,Ag)12(As,Sb)4(Se,S)13

Composition:

Molecular Weight = 2,042.97 gm

Zinc 11.52 % Zn

Copper 22.40 % Cu

Silver 6.34 % Ag

Antimony 5.96 % Sb

Arsenic 11.00 % As

Selenium 37.68 % Se

Sulfur 5.10 % S

______

100.00 %

Empirical Formula:

Cu_7.2Zn_3.6Ag_1.2As₃SbSe_9.75S_3.25

Environment:

As late stage deposits in veins cutting granite.

IMA Status:

Approved IMA 1982

Locality:

From Chameane, Puy-de-Dome, France. Link to MinDat.org Location Data.

Name Origin:

To honor Roger Giraud, of the electron microprobe laboratory of the B.R.G.M.-C.N.R.S. in Orleans, France.

Search for Giraudite 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.

Giraudite Crystallography

Cell Dimensions:

a = 10.578, Z = 2; V = 1,183.62 Den(Calc)= 5.73

Crystal System:

Isometric - HextetrahedralH-M Symbol (4 3m) Space Group: I 43m

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

By Intensity(I/I_o): 3.05(1), 1.868(0.9), 1.593(0.7),

Physical Properties of Giraudite

Cleavage:

None

Color:

Gray, Steel gray.

Density:

5.75

Diaphaniety:

Opaque

Hardness:

3.5-4 - Copper Penny-Fluorite

Luster:

Metallic

Streak:

white

Optical Properties of Giraudite

RL Color:

Light gray with a creamy tint.

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Giraudite in Air**
λ	R	∑ R(λ)
420 nm	32.20
440 nm	32.10
460 nm	31.80
480 nm	31.70
500 nm	31.60
520 nm	31.50
540 nm	31.70
560 nm	31.80
580 nm	31.70
600 nm	31.70
620 nm	31.80
640 nm	31.60
660 nm	31.50
680 nm	31.30
700 nm	30.80

**Calculated Relative Intensity Colors of Giraudite in Air**
Relative Intensity	0%	30%	60%	90%	100%	120%	150%	180%	210%	240%	270%	280%
R

Calculated Properties of Giraudite

Electron Density:

r_electron=5.09 gm/cc
note: r_Giraudite=5.73 gm/cc.

Fermion Index

Fermion Index = 0.03374
Boson Index = 0.96626

Photoelectric:

PE_Giraudite= 90.89 barns/electron
U=PE_Giraudite x r_electron= 462.28 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Giraudite is Not Radioactive

Giraudite Classification

Dana Class:

3.3.6.5 (3)Sulfides - Sulfosalts

(3.3)where 3 < z/y < 4 - (A+)i (A++)j [By Cz], A=metals, B=semi-metals, C=non-metals

(3.3.6)Tetrahedrite Group (Isometric: I4¯3m)

3.3.6.1 Tetrahedrite (Cu,Fe)12Sb4S13 I 43m 4 3m

3.3.6.2 Tennantite (Cu,Fe)12As4S13 I 43m 4 3m

3.3.6.3 Freibergite (Ag,Cu,Fe)12(Sb,As)4S13 I 43m 4 3m

3.3.6.4 Hakite (Cu,Hg)3(Sb,As)(Se,S)3 I 43m 4 3m

3.3.6.5 Giraudite (Cu,Zn,Ag)12(As,Sb)4(Se,S)13 I 43m 4 3m

3.3.6.6 Goldfieldite Cu12(Te,Sb,As)4S13 I 43m 4 3m

3.3.6.7 Argentotennantite (Ag,Cu)10(Zn,Fe)2(As,Sb)4S13 I 43m 4 3m

Strunz Class:

II/C.11-30 II - Sulfides and sulphosalts

II/C - Sulfides with metal: sulfur, selenium and tellurium = 1:1

II/C.11 - Tetrahedrite group

II/C.11-10 Tennantite (Cu,Fe)12As4S13 I 43m 4 3m

II/C.11-20 Argentotennantite (Ag,Cu)10(Zn,Fe)2(As,Sb)4S13 I 43m 4 3m

II/C.11-30 Giraudite (Cu,Zn,Ag)12(As,Sb)4(Se,S)13 I 43m 4 3m

II/C.11-40 Tetrahedrite (Cu,Fe)12Sb4S13 I 43m 4 3m

II/C.11-50 Freibergite (Ag,Cu,Fe)12(Sb,As)4S13 I 43m 4 3m

II/C.11-60 Goldfieldite Cu12(Te,Sb,As)4S13 I 43m 4 3m

II/C.11-70 Hakite (Cu,Hg)3(Sb,As)(Se,S)3 I 43m 4 3m

II/C.11-75 Mgriite Cu3AsSe3 F d3m 4/m 3 2/m

II/C.11-80 Chameanite (Cu,Fe)4As(Se,S)4 I 43m 4 3m

Other Giraudite Information

References:

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

See Also:

Links to other databases for Giraudite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas 12 -École des Mines de Paris

Search for Giraudite using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Giraudite :
AA Mineral Specimens
B and L Minerals
Crystal Vaults
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Giraudite Mineral Data :

Ask about Giraudite 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 Giraudite Specimen Label here :

Giraudite

(Cu,Zn,Ag)12(As,Sb)4(Se,S)13
Dana No: 3.3.6.5 Strunz No: II/C.11-30
Locality:

Notes: