Eyselite Mineral Data

Eyselite Mineral Data

[Fine Minerals] [What's New] [Mineral Galleries] [My Collection] [Mineral Auctions]
Dan Weinrich Fine Minerals
Full-time professional mineral dealer with over 31 years experience in mineral collecting
And 15 years selling mineral specimens on the internet and at major mineral shows

General Eyselite Information

Chemical Formula:

Fe+++Ge++++3O7(OH)

Composition:

Molecular Weight = 401.40 gm

Gallium 0.69 % Ga 0.93 % Ga₂O₃

Iron 12.94 % Fe 18.50 % Fe₂O₃

Germanium 53.91 % Ge 77.66 % GeO₂

Hydrogen 0.29 % H 2.63 % H₂O

Oxygen 32.17 % O

______ ______

100.00 % 99.72 % = TOTAL OXIDE

Empirical Formula:

Fe³⁺_0.93Ga_0.04Ge_2.98O_6.9(OH)_1.17

Environment:

Eyselite was identified in a vug on a single specimen of renierite - germanite ore with minor associated tennantite.

IMA Status:

Approved IMA 2004 (Dana # Added)

Locality:

Tsumeb mine, Tsumeb, Namibia. Link to MinDat.org Location Data.

Name Origin:

Named for Walter Hans Eysel (1935-1999), Professor of Crystallography at the Ruprecht-Karls-Universität, Heidelberg, Germany, for his contributions to the study of germanates.

Synonym:

IMA2003-052

Eyselite Image

Images:

Eyselite

Comments: Pale yellowish brown crystalline aggregate of eyselite in a vug on sulfide ore. (CanMin 42:1773).
Location: Ge-bearing ore samples from Tsumeb mine, Tsumeb, Namibia. Scale: See Scale Bar.
© Canadian Mineralogist

Images:

Eyselite

Comments: SEM photomicrograph of platy/tabular crystals of eyselite. (CanMin 42:1773).
Location: Ge-bearing ore samples from Tsumeb mine, Tsumeb, Namibia. Scale: See Scale Bar.
© Canadian Mineralogist

Eyselite Crystallography

Axial Ratios:

a:b:c =0.8542:1:0.4658

Cell Dimensions:

a = 8.302, b = 9.718, c = 4.527, Z = 2; V = 365.23 Den(Calc)= 3.65

Crystal System:

OrthorhombicSpace Group: P***

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

By Intensity(I/I_o): 2.921(1)(211), 3.681(1)(111), 2.403(0.9)(320),1.646(0.8)(322), 3.121(0.6)(220,121), 1.624(0.5)(142), 2.512(0.4)(131), 4.105(0.4)(011),

Physical Properties of Eyselite

Color:

Dirty brown yellow, Tan yellow.

Diaphaniety:

Translucent to Opaque

Fracture:

Brittle - Uneven - Very brittle fracture producing uneven fragments.

Habit:

Aggregates - Made of numerous individual crystals or clusters.

Habit:

Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).

Luster:

Vitreous (Glassy)

Streak:

brownish yellow

Optical Properties of Eyselite

Optical Data:

Biaxial (+)

NCalc= 1.72 - from Gladstone-Dale relationship (KC = 0.1985) where Ncalc=Dcalc*KC+1

Calculated Properties of Eyselite

Electron Density:

r_electron=3.39 gm/cc
note: r_Eyselite=3.65 gm/cc.

Fermion Index

Fermion Index = 0.04494
Boson Index = 0.95506

Photoelectric:

PE_Eyselite= 38.07 barns/electron
U=PE_Eyselite x r_electron= 129.15 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Eyselite is Not Radioactive

Eyselite Classification

Dana Class:

7.3.3.1 (7)Multiple Oxides

(7.3)with 2+ and higher charged cations

(7.3.3)Dana Group

7.3.3.1 Eyselite ! FeGe3O7(OH) P*** Ortho

Strunz Class:

IV/F.17-50 IV - Oxides

IV/F - Hydroxides and oxidic hydrates, water-bearing oxides with layered structure

IV/F.17 - Stottite group, Mopungite - Stottite series

IV/F.17-10 Mopungite NaSb(OH)6 P 4₁/n 4/m

IV/F.17-20 Tetrawickmanite MnSn(OH)6 P 4₁/n 4/m

IV/F.17-30 Jeanbandyite (Fe,Mn)Sn(OH)6 P 4₁/n 4/m

IV/F.17-40 Stottite FeGe(OH)6 P 4₁/n 4/m

IV/F.17-50 Eyselite FeGe3O7(OH) P*** Ortho

Other Eyselite Information

References:

NAME( CanMin, 42:1771) PHYS. PROP.(CanMin, 42:1771) OPTIC PROP.(CanMin, 42:1771)

See Also:

Links to other databases for Eyselite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 -Google Images 4 -Google Scholar 5 -MinDAT 6 -MinMax(Deutsch) 7 -MinMax(English) 8 -Mineralienatlas (Deutsch) 9 -QUT Mineral Atlas

Search for Eyselite using:

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

Visit our Advertisers for Eyselite :

AA Mineral Specimens

B & L Fine Minerals

Crystal Vaults

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

MineralsWeb Fine Minerals

Rockshop.cz

T G Fine Minerals

Wrights Rock Shop

Translate Eyselite Mineral Data :

Ask about Eyselite 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 Eyselite Specimen Label here :

Eyselite

Fe+++Ge++++3O7(OH)
Dana No: 7.3.3.1 Strunz No: IV/F.17-50
Locality:

Notes: