Efremovite Mineral Data

General Efremovite Information

Chemical Formula:

(NH4)2Mg2(SO4)3

Composition:

Molecular Weight = 372.88 gm

Magnesium 13.04 % Mg 21.62 % MgO

Hydrogen 2.16 % H - % Calc as (NH₄)₂O

Sulfur 25.80 % S 64.42 % SO₃

Nitrogen 7.51 % N 13.97 % (NH₄)₂O

Oxygen 51.49 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

(NH₄)₂Mg₂(SO₄)₃

Environment:

Secondary mineral associated with organic material and oxidizable sulfides.

IMA Status:

Approved IMA 1989

Locality:

Chelyabinsk coal Basin, Ural Mts, Russia. Link to MinDat.org Location Data.

Name Origin:

Named for Ivan Antonovich Yefremov (1907-1972), Russian geologist.

Name Pronunciation:

Efremovite + Pronunciation

Efremovite Image

Images:

Efremovite

Comments: White, massive efremovite. The mineral is hygroscopic and must be stored in a closed box.
Location: Ronneburg U deposit, Gera district, Thuringia, Germany. Scale: Picture size 6 mm.
© Thomas Witzke / Abraxas-Verlag

Efremovite Crystallography

Cell Dimensions:

a = 9.99, Z = 4; V = 997.00 Den(Calc)= 2.48

Crystal System:

Isometric - Tetartoidal H-M Symbol (2 3) Space Group: P 2₁3

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

By Intensity(I/I_o): 3.15(1), 4.07(0.7), 2.668(0.5),

Physical Properties of Efremovite

Cleavage:

None

Color:

Gray white, White.

Diaphaneity:

Subtranslucent to Opaque

Hardness:

2 - Gypsum

Luster:

Vitreous - Dull

Streak:

white

Optical Properties of Efremovite

Gladstone-Dale:

CI calc= -0.41 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2218,KC= 0.1573
Ncalc = 1.39

Optical Data:

Isotropic, n=1.55.

Calculated Properties of Efremovite

Electron Density:

Bulk Density (Electron Density)=2.53 gm/cc
note: Specific Gravity of Efremovite =2.48 gm/cc.

Fermion Index:

Fermion Index = 0.09
Boson Index = 0.91

Photoelectric:

PE_Efremovite= 1.85 barns/electron
U=PE_Efremovite x rElectron Density= 4.68 barns/cc.

Radioactivity:

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

Efremovite Classification

Dana Class:

28.04.04.03 (28)Anhydrous Acid and Sulfates

(28.04)with miscellaneous formulae

(28.04.04)Langbeinite Series

28.04.04.01 Langbeinite K2Mg2(SO4)3 P 2₁3 2 3

28.04.04.02 Manganolangbeinite K2Mn2(SO4)3 P 2₁3 2 3

28.04.04.03 Efremovite (NH4)2Mg2(SO4)3 P 2₁3 2 3

Strunz Class:

07.AC.10 07 - SULFATES (SELENATES, TELLURATES)

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

07.AC -With medium-sized and large cations

07.AC.10 Efremovite (NH4)2Mg2(SO4)3 P 2₁3 2 3

07.AC.10 Manganolangbeinite K2Mn2(SO4)3 P 2₁3 2 3

07.AC.10 Langbeinite K2Mg2(SO4)3 P 2₁3 2 3

Other Efremovite Information

References:

PHYS. PROP.(Am.Min.,Vol.76,p299,1991) OPTIC PROP.(Am.Min.,Vol.76,p299,1991)

See Also:

Links to other databases for Efremovite :
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 Efremovite Specimen Label here :

Efremovite

(NH4)2Mg2(SO4)3
Dana No: 28.04.04.03 Strunz No: 07.AC.10
Locality:

Notes:

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