Mackayite Mineral Data

General Mackayite Information

Chemical Formula:

Fe+++Te2O5(OH)

Composition:

Molecular Weight = 408.05 gm

Iron 13.69 % Fe 19.57 % Fe₂O₃

Tellurium 62.54 % Te 78.22 % TeO₂

Hydrogen 0.25 % H 2.21 % H₂O

Oxygen 23.53 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Fe³⁺Te₂O₅(OH)

Environment:

Secondary mineral in telluride-bearing ores.

IMA Status:

Valid Species (Pre-IMA) 1944

Locality:

Mohawk mine, Goldfield, Nevada. Link to MinDat.org Location Data.

Name Origin:

Named for John William Mackay (1831-1902), mine operator, Comstock Lode, and benefactor of the Mackay School of Mines, University of Nevada.

Name Pronunciation:

Mackayite + Pronunciation

Synonym:

ICSD 100139

PDF 29-730

Mackayite Image

Images:

Mackayite

Comments: Greenish brown crystals of mackayite on matrix.
Location: McGuinnity shaft, Goldfield, Esmeralda County, Nevada, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Mackayite Crystallography

Axial Ratios:

a:c = 1:1.27178

Cell Dimensions:

a = 11.704, c = 14.885, Z = 16; V = 2,039.00 Den(Calc)= 5.32

Crystal System:

Tetragonal - Ditetragonal Dipyramidal H-M Symbol (4/m 2/m 2/m) Space Group: I 4₁/acd

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

By Intensity(I/I_o): 3.17(1), 1.61(0.9), 3.32(0.8),

Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize
Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu
Help on Above

Forms: ( 1 1 2) ( 1 1 0) ( 1 0 0)

Warning: this java applet does not work in some browsers because of security restrictions.

Physical Properties of Mackayite

Cleavage:

None

Color:

Brownish green, Yellow green, Olive green.

Density:

4.86

Diaphaneity:

Transparent

Fracture:

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

Hardness:

4.5 - Between Fluorite and Apatite

Luster:

Vitreous (Glassy)

Streak:

light green

Optical Properties of Mackayite

Dichroism (e):

green.

Dichroism (w):

yellowish green.

Gladstone-Dale:

CI meas= -0.091 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.004 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2256,KPDmeas= 0.2469,KC= 0.2264
Ncalc = 2.1 - 2.2

Optical Data:

Uniaxial (+), w=2.19, e=2.21, bire=0.0200.

Calculated Properties of Mackayite

Electron Density:

Bulk Density (Electron Density)=4.67 gm/cc
note: Specific Gravity of Mackayite =5.32 gm/cc.

Fermion Index:

Fermion Index = 0.05
Boson Index = 0.95

Photoelectric:

PE_Mackayite= 223.27 barns/electron
U=PE_Mackayite x rElectron Density=1,042.10 barns/cc.

Radioactivity:

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

Mackayite Classification

Dana Class:

34.06.01.01 (34)Selenites - Tellurites - Sulfites

(34.06)Dana Type

(34.06.01)Dana Group

34.06.01.01 Mackayite FeTe2O5(OH) I 4₁/acd 4/m 2/m 2/m

Strunz Class:

04.JL.10 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.J - Arsenites, Antimonites, Bismuthites, Sulfites,

04.JL -Tellurites with additional anions, without H2O

04.JL.10 Mackayite FeTe2O5(OH) I 4₁/acd 4/m 2/m 2/m

Other Mackayite Information

References:

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

See Also:

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

Search for Mackayite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Mackayite :

Ask about Mackayite 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 Mackayite Specimen Label here :

Mackayite

Fe+++Te2O5(OH)
Dana No: 34.06.01.01 Strunz No: 04.JL.10
Locality:

Notes:

Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.