Stewartite Mineral Data

General Stewartite Information

Chemical Formula:

Mn++Fe+++2(PO4)2(OH)2•8(H2O)

Composition:

Molecular Weight = 534.71 gm

Manganese 10.27 % Mn 13.27 % MnO

Iron 20.89 % Fe 29.87 % Fe₂O₃

Phosphorus 11.59 % P 26.55 % P₂O₅

Hydrogen 3.39 % H 30.32 % H₂O

Oxygen 53.86 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mn²⁺Fe³⁺₂(PO₄)₂(OH)₂•8(H₂O)

Environment:

Granitic lithia-bearing pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1912

Locality:

Stuart mine, Queen Mountains, Pala, San Diego Co., California. Link to MinDat.org Location Data.

Name Origin:

Named after it's locality.

Name Pronunciation:

Stewartite + Pronunciation

Synonym:

ICSD 6204

PDF 5-110

Stewartite Image

Images:

Stewartite Rockbridgeite

Comments: Pointed, brownish yellow stewartite crystals on massive, dark rockbridgeite.
Location: Hagendorf, Bavaria, Germany. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Stewartite Crystallography

Axial Ratios:

a:b:c =0.9743:1:0.6768

Cell Dimensions:

a = 10.398, b = 10.672, c = 7.223, Z = 2; alpha = 90.1°, beta = 109.1°, gamma = 71.83° V = 719.63 Den(Calc)= 2.47

Crystal System:

Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1

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

By Intensity(I/I_o): 9.98(1), 2.99(0.4), 3.93(0.4),

Physical Properties of Stewartite

Cleavage:

{???} Good

Color:

Brownish yellow, Yellow, Orange.

Density:

2.94

Diaphaneity:

Transparent to translucent

Habit:

Cryptocrystalline - Occurs as crystals too small to distinguish with the naked eye.

Habit:

Fibrous - Crystals made up of fibers.

Hardness:

3 - Calcite

Luminescence:

Non-fluorescent.

Streak:

white

Optical Properties of Stewartite

Gladstone-Dale:

CI meas= 0.188 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.037 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2617,KPDmeas= 0.2207,KC= 0.2719
Ncalc = 1.67 - 1.8

Optical Data:

Biaxial (-), a=1.612-1.63, b=1.653-1.658, g=1.66-1.681, bire=0.0480-0.0510

Calculated Properties of Stewartite

Electron Density:

Bulk Density (Electron Density)=2.50 gm/cc
note: Specific Gravity of Stewartite =2.48 gm/cc.

Fermion Index:

Fermion Index = 0.0046920033
Boson Index = 0.9953079967

Photoelectric:

PE_Stewartite= 9.22 barns/electron
U=PE_Stewartite x rElectron Density= 23.01 barns/cc.

Radioactivity:

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

Stewartite Classification

Dana Class:

42.11.10.02 (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen

(42.11)where (AB)4 (XO4)3 Zq � x(H2O)

(42.11.10)Laueite Group

42.11.10.01 Laueite MnFe2(PO4)2(OH)2•8(H2O) P1 1

42.11.10.02 Stewartite MnFe2(PO4)2(OH)2•8(H2O) P1 1

42.11.10.03 Pseudolaueite MnFe2(PO4)2(OH)2•7-8(H2O) P 2₁/a 2/m

42.11.10.04 Ushkovite MgFe2(PO4)2(OH)2•8(H2O) P1 1

42.11.10.05 Ferrolaueite! FeFe2(PO4)2(OH)2•8(H2O) Tri

Strunz Class:

08.DC.30 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DC -With only medium-sized cations, (OH, etc.):RO4 = 1:1 and < 2:1

08.DC.30 Gordonite MgAl2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Ferrolaueite! FeFe2(PO4)2(OH)2•8(H2O) Tri

08.DC.30 Mangangordonite (Mn,Fe,Mg)Al2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Laueite MnFe2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Sigloite FeAl2(PO4)2(OH)3•5(H2O) P1 1

08.DC.30 Pseudolaueite MnFe2(PO4)2(OH)2•7-8(H2O) P 2₁/a 2/m

08.DC.30 Paravauxite FeAl2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Stewartite MnFe2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Ushkovite MgFe2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Kastningite! (Mn,Fe,Mg)Al2(PO4)2(OH)2•8(H2O) P1 1

08.DC.30 Maghrebite! MgAl2(AsO4)2(OH)2•8H2O P1 1

Other Stewartite Information

References:

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

See Also:

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

Stewartite

Mn++Fe+++2(PO4)2(OH)2•8(H2O)
Dana No: 42.11.10.02 Strunz No: 08.DC.30
Locality:

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