Mohrite Mineral Data

General Mohrite Information

Chemical Formula:

(NH4)2Fe++(SO4)2•6(H2O)

Composition:

Molecular Weight = 392.14 gm

Iron 14.24 % Fe 18.32 % FeO

Hydrogen 2.06 % H - % Calc as (NH₄)₂O

Hydrogen 3.08 % H 27.56 % H₂O

Sulfur 16.35 % S 40.83 % SO₃

Nitrogen 7.14 % N 13.28 % (NH₄)₂O

Oxygen 57.12 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

(NH₄)₂Fe²⁺(SO₄)₂•6(H₂O)

Environment:

Boriferous fumaroles and geysers.

IMA Status:

Approved IMA 1964

Locality:

Travale, near Montieri, Val di Cecina, Tuscany, Italy. Link to MinDat.org Location Data.

Name Origin:

Named for Karl Friedrich Mohr (1806-1879), German analytical chemist, for whom the synthetic compound has long been named.

Name Pronunciation:

Mohrite

Synonym:

ICSD 65669

Mohr's salt

PDF 35-764

Mohrite Image

Images:

Mohrite

Comments: Opaque botryoidal mohrite aggregate.
Location: Saint Etienne, Layonnais, Languedoc, Loire, France. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Mohrite Crystallography

Axial Ratios:

a:b:c =0.4944:1:0.7367

Cell Dimensions:

a = 6.237, b = 12.613, c = 9.292, Z = 2; beta = 106.883° V = 699.47 Den(Calc)= 1.86

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/c

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

By Intensity(I/I_o): 4.2(1), 3.79(0.55), 4.13(0.55),

Physical Properties of Mohrite

Cleavage:

{102} Perfect, {010} Distinct

Color:

Light green.

Density:

1.8 - 1.862, Average = 1.83

Diaphaneity:

Transparent

Hardness:

2-2.5 - Gypsum-Finger Nail

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Mohrite

Gladstone-Dale:

CI meas= -0.328 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.307 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.262,KPDmeas= 0.2661,KC= 0.2004
Ncalc = 1.36 - 1.37

Optical Data:

Biaxial (+), a=1.48-1.486, g=1.486-1.497, bire=0.0060-0.0110, 2V(Meas)=75.

Calculated Properties of Mohrite

Electron Density:

Bulk Density (Electron Density)=1.94 gm/cc
note: Specific Gravity of Mohrite =1.86 gm/cc.

Fermion Index:

Fermion Index = 0.07
Boson Index = 0.93

Photoelectric:

PE_Mohrite= 5.07 barns/electron
U=PE_Mohrite x rElectron Density= 9.81 barns/cc.

Radioactivity:

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

Mohrite Classification

Dana Class:

29.03.07.01 (29)Hydrated Acid and Sulfates

(29.03)where (A+)2 B (XO4)2 ï¿½ x(H2O)

(29.03.07)Mohrite Group (Ammonia bearing)

29.03.07.01 Mohrite (NH4)2Fe(SO4)2•6(H2O) P 2₁/c 2/m

29.03.07.02 Boussingaultite (NH4)2Mg(SO4)2•6(H2O) P 2₁/a 2/m

29.03.07.03 Nickelboussingaultite (NH4)2(Ni,Mg)(SO4)2•6(H2O) P 2₁/a 2/m

Strunz Class:

07.CC.60 07 - SULFATES (SELENATES, TELLURATES)

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

07.CC -With medium-sized and large cations

07.CC.60 Boussingaultite (NH4)2Mg(SO4)2•6(H2O) P 2₁/a 2/m

07.CC.60 Cyanochroite K2Cu(SO4)2•6(H2O) P 2₁/a 2/m

07.CC.60 Mohrite (NH4)2Fe(SO4)2•6(H2O) P 2₁/c 2/m

07.CC.60 Picromerite K2Mg(SO4)2•6(H2O) P 2₁/a 2/m

07.CC.60 Nickelboussingaultite (NH4)2(Ni,Mg)(SO4)2•6(H2O) P 2₁/a 2/m

Other Mohrite Information

References:

NAME( AntBidBlaNic5) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Mohrite :
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

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Print or Cut-and-Paste your Mohrite Specimen Label here :

Mohrite

(NH4)2Fe++(SO4)2•6(H2O)
Dana No: 29.03.07.01 Strunz No: 07.CC.60
Locality:

Notes:

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