Carnallite Mineral Data

General Carnallite Information

Chemical Formula:

KMgCl3•6(H2O)

Composition:

Molecular Weight = 277.85 gm

Potassium 14.07 % K 16.95 % K₂O

Magnesium 8.75 % Mg 14.51 % MgO

Hydrogen 4.35 % H 38.90 % H₂O

Chlorine 38.28 % Cl 38.28 % Cl

- % Cl -8.64 % -O=Cl₂

Oxygen 34.55 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

KMgCl₃•6(H₂O)

Environment:

Marine evaporites.

IMA Status:

Valid Species (Pre-IMA) 1856

Locality:

Stassfurt, Province of Saxony, Germany. Link to MinDat.org Location Data.

Name Origin:

Named after the German mining engineer, R. von Carnall (1804-1874).

Synonym:

Almeraite - mixture of carnallite and halite.

ICSD 64691

PDF 24-869

Carnallite Image

Images:

Carnallite Rinneite

Comments: Orange to light brown rinneite with colorless carnallite.
Location: Merkers, Bad Salzungen, Rhön, Thuringia, Germany. Scale: Picture size 4 mm.
© Thomas Witzke / Abraxas-Verlag

Images:

Carnallite

Comments: Clear crystalline massive carnallite.
Location: Stassfurt, Sachsen-Anhalt, Germany. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Images:

Carnallite Rokuhnite

Comments: Reddish brown rokuhnite, with carnallite (deliquescent).
Location: Salzdetfurth Mine, Hildesheim, near Hanover, Niedersachsen, Germany. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Carnallite Crystallography

Axial Ratios:

a:b:c =0.5956:1:1.4056

Cell Dimensions:

a = 9.56, b = 16.05, c = 22.56, Z = 12; V = 3,461.56 Den(Calc)= 1.60

Crystal System:

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

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

By Intensity(I/I_o): 3.3(1), 2.92(0.7), 4.65(0.5),

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 0 1) ( 1 1 1) ( 1 1 0) ( 1 0 0) ( 0 0 1)

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

Schlemper E O , Sen Gupta P K , Zoltai T , American Mineralogist , 70 (1985) p.1309-1313, Refinement of the structure of carnallite, Mg(H2O)6KCl3

View Additional jPOWD Structure files for Carnallite
[1]

Physical Properties of Carnallite

Cleavage:

None

Color:

Blue, Colorless, Yellow, White, Red.

Density:

1.6

Diaphaneity:

Transparent to translucent

Fracture:

Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz).

Habit:

Fibrous - Crystals made up of fibers.

Habit:

Massive - Granular - Common texture observed in granite and other igneous rock.

Habit:

Pseudo Hexagonal - Crystals show a hexagonal outline.

Hardness:

2.5 - Finger Nail

Luminescence:

Non-fluorescent.

Luster:

Greasy (Oily)

Streak:

white

Optical Properties of Carnallite

Optical Data:

Biaxial (+), a=1.467, b=1.4755, g=1.494, bire=0.0270, 2V(Calc)=70, 2V(Meas)=70. Dispersion none.

Calculated Properties of Carnallite

Electron Density:

Bulk Density (Electron Density)=1.64 gm/cc
note: Specific Gravity of Carnallite =1.60 gm/cc.

Fermion Index:

Fermion Index = 0.0089366811
Boson Index = 0.9910633189

Photoelectric:

PE_Carnallite= 4.07 barns/electron
U=PE_Carnallite x r_electron= 6.66 barns/cc.

Radioactivity:

GRapi = 207.54 (Gamma Ray American Petroleum Institute Units)
Concentration of Carnallite per GRapi unit = 0.48 (%)

Estimated Radioactivity from Carnallite - barely detectable

Carnallite Classification

Dana Class:

11.01.02.01 (11)Halide Complexes; Alumino-fluorides

(11.01)where (A)m B (X)3

(11.01.02)Dana Group

11.01.02.01 Carnallite KMgCl3•6(H2O) Pcna 2/m 2/m 2/m

Strunz Class:

03.BA.10 03 - HALIDES

03.B - Simple Halides, with H2O

03.BA -M:X = 1:1 and 2:3

03.BA.10 Carnallite KMgCl3•6(H2O) Pcna 2/m 2/m 2/m

Other Carnallite Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Mason68)

See Also:

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

Search for Carnallite using:

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

Visit our Advertisers for Carnallite :

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

Ask about Carnallite 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 Carnallite Specimen Label here :

Carnallite

KMgCl3•6(H2O)
Dana No: 11.01.02.01 Strunz No: 03.BA.10
Locality:

Notes: