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 % K2 O
Calcium 11.36 % Ca 15.89 % CaO
Copper 18.01 % Cu 22.54 % CuO
Hydrogen 0.57 % H 5.11 % H2 O
Sulfur 18.17 % S 45.38 % SO3
Oxygen 40.81 % O
______ ______
100.00 % 102.27 % = TOTAL OXIDE
Empirical Formula:
K2 Ca2 Cu2 (SO4 )4 •2(H2 O)
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 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 - Prismatic H-M Symbol (2/m) Space Group: C 2/c
X Ray Diffraction:
By Intensity(I/Io ): 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 java applet does not work in some browsers because of security restrictions.
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:
PELeightonite = 11.32 barns/electronU=PELeightonite 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 :
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
Espa�ol
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:
Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.