Leightonite Mineral Data

General Leightonite Information

Chemical Formula:

K2Ca2Cu(SO4)4•2(H2O)

Composition:

Molecular Weight = 705.73 gm

Potassium 11.08 % K 13.35 % K₂O

Calcium 11.36 % Ca 15.89 % CaO

Copper 18.01 % Cu 22.54 % CuO

Hydrogen 0.57 % H 5.11 % H₂O

Sulfur 18.17 % S 45.38 % SO₃

Oxygen 40.81 % O

______ ______

100.00 % 102.27 % = TOTAL OXIDE

Empirical Formula:

K₂Ca₂Cu₂(SO₄)₄•2(H₂O)

Environment:

Arid environments in oxidized copper sulfide ore deposits with low acidity. Structurally related to polyhalite.

IMA Status:

Valid Species (Pre-IMA) 1938

Locality:

Chuquicamata, Antofagasta, Chile. Link to MinDat.org Location Data.

Name Origin:

Named for T. Leighton, mineralogist at the University of Sanitago, Chile.

Name Pronunciation:

Leightonite + Pronunciation

Leightonite Image

Images:

Leightonite

Comments: Pale Leightonite with dark green atacamite.
Location: Chuquicamata, Antofagasta, Chile. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Leightonite Crystallography

Axial Ratios:

a:b:c =1.5544:1:1.3468

Cell Dimensions:

a = 11.654, b = 7.497, c = 10.097, Z = 2; beta = 125.21° V = 720.78 Den(Calc)= 3.25

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: C 2/c

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

By Intensity(I/I_o): 2.9(1), 3.18(0.6), 1.781(0.3),

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: ( 0 3 1) ( 1 3 0) ( 0 1 0) ( 1 3 1) ( 1 0 1) ( 1 1 0)

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

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

Menchetti S , Bindi L , Bonazzi P , Olmi F , American Mineralogist , 87 (2002) p.721-725, Disordered distribution of Cu in the crystal structure of leightonite,, K2Ca2Cu(SO4)4.2H2O

Physical Properties of Leightonite

Cleavage:

None

Color:

Blue green, Light blue.

Density:

2.95

Diaphaneity:

Transparent to Translucent

Habit:

Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).

Hardness:

3 - Calcite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Leightonite

Gladstone-Dale:

CI meas= -0.017 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.077 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1805,KPDmeas= 0.1989,KC= 0.1955
Ncalc = 1.58 - 1.64

Optical Data:

Biaxial (-), a=1.578, b=1.587, g=1.595, bire=0.0170, 2V(Calc)=86, 2V(Meas)=86.15.

Calculated Properties of Leightonite

Electron Density:

Bulk Density (Electron Density)=2.91 gm/cc
note: Specific Gravity of Leightonite =2.95 gm/cc.

Fermion Index:

Fermion Index = 0.0017264599
Boson Index = 0.9982735401

Photoelectric:

PE_Leightonite= 11.32 barns/electron
U=PE_Leightonite x r_electron= 32.95 barns/cc.

Radioactivity:

GRapi = 157.65 (Gamma Ray American Petroleum Institute Units)
Concentration of Leightonite per GRapi unit = 0.63 (%)

Estimated Radioactivity from Leightonite - barely detectable

Leightonite Classification

Dana Class:

29.04.05.02 (29)Hydrated Acid and Sulfates

(29.04)where (A+)2 Bn (XO4)p · x(H2O)

(29.04.05)Dana Group

29.04.05.01 Polyhalite K2Ca2Mg(SO4)4•2(H2O) P 1,P1 Tri

29.04.05.02 Leightonite K2Ca2Cu(SO4)4•2(H2O) C 2/c 2/m

Strunz Class:

07.CC.70 07 - SULFATES (SELENATES, TELLURATES)

07.C - Sulfates (selenates, etc.) without Additional Anions, with H2O

07.CC -With medium-sized and large cations

07.CC.70 Leightonite K2Ca2Cu(SO4)4•2(H2O) C 2/c 2/m

Other Leightonite Information

References:

NAME( AmMin, Vol 87, p 721) PHYS. PROP.(AmMin, Vol 87, p 721) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Leightonite :
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

Search for Leightonite using:

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

Visit our Advertisers for Leightonite :

A Bijoux Google Search for Leightonite
Adam's Minerals Google Search for Leightonite
Cape Minerals Google Search for Leightonite
Dakota Matrix Minerals Google Search for Leightonite
Excalibur Mineral Corp. Google Search for Leightonite
Exceptional Minerals Google Search for Leightonite
John Betts Fine Minerals Search for Leightonite
McDougall Minerals Google Search for Leightonite
Mineral News Website Link
Rock and Mineral Shows Google Search for Leightonite
Weinrich Minerals, Inc. Google Search for Leightonite

Ask about Leightonite 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 Leightonite Specimen Label here :

Leightonite

K2Ca2Cu(SO4)4•2(H2O)
Dana No: 29.04.05.02 Strunz No: 07.CC.70
Locality:

Notes: