Gedrite Mineral Data

[What's New] [Mineral Galleries] [About Us] [Contacts] [Login]
At AA Mineral Specimens, we source quality Mineral Specimens, Fossils, Gemstones,
Decorative Stones, Lapidary Material and Specimen Sets world-wide

General Gedrite Information

Chemical Formula:

[ ]Mg5Al2Si6Al2O22(OH)2

Composition:

Molecular Weight = 783.97 gm

Magnesium 15.50 % Mg 25.71 % MgO

Aluminum 13.77 % Al 26.01 % Al₂O₃

Silicon 21.49 % Si 45.98 % SiO₂

Hydrogen 0.26 % H 2.30 % H₂O

Oxygen 48.98 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg₅Al₂(Si₆Al₂O₂₂)(OH)₂

IMA Status:

Valid Species (Pre-IMA) 1836

Locality:

Heas Valley near Gedres, France. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Name Pronunciation:

Gedrite

Synonym:

ICSD 34833

PDF 13-506

Gedrite Image

Images:

Gedrite

Comments: Back prismatic crystalline gedrite in rock.
Location: Schissgruvan, near Ludvika, Dalarna, Kopparberg, Sweden. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Images:

Gedrite Magnesiogedrite

Comments: Dark gray cleavage fragment of magnesiogedrite (gedrite).
Location: Bamble, Telemark, Norway. Scale: See Image.
© Rruff Database

Gedrite Crystallography

Axial Ratios:

a:b:c =1.0393:1:0.2964

Cell Dimensions:

a = 18.594, b = 17.89, c = 5.304, Z = 4; V = 1,764.36 Den(Calc)= 2.95

Crystal System:

Orthorhombic - DipyramidalH-M Symbol (2/m 2/m 2/m) Space Group: P nma

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

By Intensity(I/I_o): 3.06(1), 8.27(0.8), 3.27(0.7),8.97(0.5), 2.5(0.4), 3.35(0.4), 3.65(0.4), 4.48(0.4),

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

Papike J J , Ross M , American Mineralogist , 55 (1970) p.1945-1972, Gedrites: Crystal structures and intracrystalline cation distributions, sample 001

View Additional jPOWD Structure files for Gedrite
[1]

Physical Properties of Gedrite

Cleavage:

{210} Perfect, {100} Indistinct, {001} Indistinct

Color:

Brown, Brown green, Green, Gray, Gray white.

Density:

3.15 - 3.57, Average = 3.36

Diaphaneity:

Transparent to Subopaque

Habit:

Massive - Fibrous - Distinctly fibrous fine-grained forms.

Hardness:

5.5-6 - Knife Blade-Orthoclase

Luster:

Vitreous - Silky

Streak:

gray white

Optical Properties of Gedrite

Gladstone-Dale:

CI meas= 0.029 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= -0.105 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2307,KPDmeas= 0.2026,KC= 0.2087
Ncalc = 1.62 - 1.75

Optical Data:

Biaxial (-), a=1.671, b=1.681, g=1.69, bire=0.0190, 2V(Calc)=86, 2V(Meas)=75.

Calculated Properties of Gedrite

Electron Density:

Bulk Density (Electron Density)=3.34 gm/cc
note: Specific Gravity of Gedrite =3.36 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Gedrite= 1.58 barns/electron
U=PE_Gedrite x rElectron Density= 5.27 barns/cc.

Radioactivity:

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

Gedrite Classification

Dana Class:

66.01.02.06 (66)Inosilicate Double-Width Unbranched Chains, W=2

(66.01)with P=2 amphibole configuration

(66.01.02)Dana Group

66.01.02.01 Magnesioanthophyllite? (Mg,Fe)7Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.02 Anthophyllite []Mg7Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.02a Protoanthophyllite! (Mg,Fe)7Si8O22(OH)2 Pnmn 2/m 2/m 2/m

66.01.02.03 Ferro-anthophyllite []Fe7Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.03a Protoferro-anthophyllite! (Fe,Mn)2(Fe,Mg)5(Si4O11)2(OH)2 Pnmn 2/m 2/m 2/m

66.01.02.03b Protomangano-ferro-anthophyllite! (Mn,Fe)2(Fe,Mg)5(Si4O11)2(OH)2 Pnmn 2/m 2/m 2/m

66.01.02.04 Sodicanthophyllite NaMg7Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.04a Sodic-ferro-anthophyllite! NaFe7Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.05 Magnesiogedrite? (Mg,Fe)5Al2Si6Al2O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.06 Gedrite []Mg5Al2Si6Al2O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.07 Ferrogedrite []Fe5Al2Si6Al2O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.07a Sodic-ferrogedrite! NaFe6AlSi6Al2O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.08 Sodicgedrite NaMg6AlSi6Al2O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.09 Magnesioholmquistite Li2(Mg,Fe)3Al2Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.10 Holmquistite [](Li2Mg3Al2)Si8O22(OH)2 P nma 2/m 2/m 2/m

66.01.02.11 Ferroholmquistite [](Li2Fe3Al2)Si8O22(OH)2 P nma 2/m 2/m 2/m

Strunz Class:

09.DE.05 09 - SILICATES (Germanates)

09.D - Inosilicates* Structural terminology according to Liebau (1985)

09.DE -Inosilicates with 2-periodic double chains, Si4O11; amphibole family

09.DE.05 Ferro-anthophyllite []Fe7Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Anthophyllite []Mg7Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Ferrogedrite []Fe5Al2Si6Al2O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Gedrite []Mg5Al2Si6Al2O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Ferroholmquistite [](Li2Fe3Al2)Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Holmquistite [](Li2Mg3Al2)Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Cummingtonite []Mg7Si8O22(OH)2 C 2/m 2/m

09.DE.05 Clinoferroholmquistite [](Li2Fe3Al2)Si8O22(OH)2 C 2/m 2/m

09.DE.05 Grunerite []Fe7Si8O22(OH)2 C 2/m 2/m

09.DE.05 Magnesiocummingtonite (Mg,Fe)7Si8O22(OH)2 C 2/m 2/m

09.DE.05 Manganogrunerite []Mn2Fe5Si8O22(OH) C 2/m 2/m

09.DE.05 Magnesioanthophyllite? (Mg,Fe)7Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Protomangano-ferro-anthophyllite! (Mn,Fe)2(Fe,Mg)5(Si4O11)2(OH)2 Pnmn 2/m 2/m 2/m

09.DE.05 Sodicgedrite NaMg6AlSi6Al2O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Sodic-ferro-anthophyllite! NaFe7Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Sodic-ferrogedrite! NaFe6AlSi6Al2O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Sodicanthophyllite NaMg7Si8O22(OH)2 P nma 2/m 2/m 2/m

09.DE.05 Permanganogrunerite! []Mn4(Fe)3(Si8O22)(OH)2 C 2/m 2/m

09.DE.05 Protoferro-anthophyllite! (Fe,Mn)2(Fe,Mg)5(Si4O11)2(OH)2 Pnmn 2/m 2/m 2/m

09.DE.05 Fluoro-sodic-pedrizite! NaLi2(Mg2Al2Li)S5Si8O22F2 C 2/m 2/m

09.DE.05 Sodic-ferri-ferropedrizite! NaLi2(Fe2Fe3)Si8O22(OH)2 C 2/m 2/m

09.DE.05 Manganocummingtonite Na(Na,Mn)2(Mg4,Fe)5Si8O22(OH)2 C 2/m 2/m

09.DE.05 Protoanthophyllite! (Mg,Fe)7Si8O22(OH)2 Pnmn 2/m 2/m 2/m

09.DE.05 Ferri-clinoferroholmquistite! []Li2(Fe2Fe3)Si8O22(OH)2 C 2/m 2/m

09.DE.05 Sodic-ferripedrizite! Na(LiNa)(Fe2Mg2Li)Si8O22(OH,F)2 C 2/m 2/m

09.DE.05 Ferripedrizite! NaLi2(Fe2Mg2Li)Si8O22(OH)2 C 2/m 2/m

Other Gedrite Information

References:

NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

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

Search for Gedrite using:

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

Visit our Advertisers for Gedrite :

AA Mineral Specimens

B & L Fine Minerals

Crystalarium.com

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

Dakota Matrix

Desert Winds Gems and Minerals

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

Wrights Rock Shop

Translate Gedrite Mineral Data :

Ask about Gedrite 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 Gedrite Specimen Label here :

Gedrite

[ ]Mg5Al2Si6Al2O22(OH)2
Dana No: 66.01.02.06 Strunz No: 09.DE.05
Locality:

Notes: