Pyroaurite Mineral Data

General Pyroaurite Information

Chemical Formula:

Mg6Fe+++2(CO3)(OH)16•4(H2O)

Composition:

Molecular Weight = 661.71 gm

Magnesium 22.04 % Mg 36.55 % MgO

Iron 16.88 % Fe 24.13 % Fe₂O₃

Hydrogen 3.66 % H 32.67 % H₂O

Carbon 1.82 % C 6.65 % CO₂

Oxygen 55.61 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg₆Fe³⁺₂(CO₃)(OH)₁₆•4(H₂O)

IMA Status:

Valid Species (Pre-IMA) 1865

Locality:

Langbanshyttan, Sweden. Link to MinDat.org Location Data.

Name Origin:

From the Greek, pyro and the Latin aurium, "fire" and "golden" because of the gold-like submetallic scales present in its type locality.

Name Pronunciation:

Pyroaurite + Pronunciation

Synonym:

ICSD 6295

PDF 25-521

Pyroaurite Image

Images:

Pyroaurite

Comments: Green, hexagonal plates of pyroaurite in quartz.
Location: Varmland, Sweden. Scale: Crystal size 1 mm.
© Tom Loomis / Dakota Matrix

Images:

Pyroaurite

Comments: Golden yellow platy crystals of pyroaurite to 1mm on matrix.
Location: Langban mine, Varmland, Sweden. Scale: Picture size 1 cm.
© Tom Loomis / Dakota Matrix

Pyroaurite Crystallography

Axial Ratios:

a:c = 1:7.51857

Cell Dimensions:

a = 6.19, c = 46.54, Z = 3; V = 1,544.32 Den(Calc)= 2.13

Crystal System:

Trigonal - Hexagonal Scalenohedral H-M Symbol (3 2/m) Space Group: R 3m

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

By Intensity(I/I_o): 7.77(1), 3.89(0.8), 2.62(0.5),

Physical Properties of Pyroaurite

Cleavage:

{0001} Perfect

Color:

Brownish yellow, Brown white, Colorless, Greenish, Yellowish white.

Density:

2.07

Diaphaneity:

Transparent

Fracture:

Flexible - Flexible fragments.

Habit:

Fibrous - Crystals made up of fibers.

Habit:

Tabular - Form dimensions are thin in one direction.

Hardness:

2.5 - Finger Nail

Luster:

Pearly

Streak:

white

Optical Properties of Pyroaurite

Gladstone-Dale:

CI meas= 0.025 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.052 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2599,KPDmeas= 0.2674,KC= 0.2742
Ncalc = 1.57 - 1.58

Optical Data:

Uniaxial (-), e=1.543, w=1.564, bire=0.0210.

Calculated Properties of Pyroaurite

Electron Density:

Bulk Density (Electron Density)=2.11 gm/cc
note: Specific Gravity of Pyroaurite =2.07 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Pyroaurite= 5.43 barns/electron
U=PE_Pyroaurite x rElectron Density= 11.48 barns/cc.

Radioactivity:

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

Pyroaurite Classification

Dana Class:

16b.06.02.03 (16b)Carbonates - Hydroxyl or Halogen

(16b.06)Dana Type

(16b.06.02)Sjorgrenite-Hydrotalcite Group (Hydrotalcite Subgroup:Rhombohedral)

16b.06.02.01 Hydrotalcite Mg6Al2(CO3)(OH)16•4(H2O) R 3m 3 2/m

16b.06.02.02 Stichtite Mg6Cr2(CO3)(OH)16•4(H2O) R 3m 3 2/m

16b.06.02.03 Pyroaurite Mg6Fe2(CO3)(OH)16•4(H2O) R 3m 3 2/m

16b.06.02.04 Desautelsite Mg6Mn2(CO3)(OH)16•4(H2O) R 3m or R 3m Trig

16b.06.02.05 Droninoite! Ni3FeCl(OH)8•2H2O R 3m, R 3m or R 32 Trig

Strunz Class:

05.DA.50 05 - CARBONATES (NITRATES)

05.D - Carbonates with Additional Anions, with H2O

05.DA -With medium-sized cations

05.DA.50 Desautelsite Mg6Mn2(CO3)(OH)16•4(H2O) R 3m or R 3m Trig

05.DA.50 Comblainite Ni6Co2(CO3)(OH)16•4(H2O) R 3m 3 2/m

05.DA.50 Hydrotalcite Mg6Al2(CO3)(OH)16•4(H2O) R 3m 3 2/m

05.DA.50 Pyroaurite Mg6Fe2(CO3)(OH)16•4(H2O) R 3m 3 2/m

05.DA.50 Reevesite Ni6Fe2(CO3)(OH)16•4(H2O) R 3m 3 2/m

05.DA.50 Stichtite Mg6Cr2(CO3)(OH)16•4(H2O) R 3m 3 2/m

05.DA.50 Takovite Ni6Al2(OH)16(CO3,OH)•4(H2O) R 3m 3 2/m

Other Pyroaurite Information

References:

NAME( Ford32) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

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

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

Pyroaurite

Mg6Fe+++2(CO3)(OH)16•4(H2O)
Dana No: 16b.06.02.03 Strunz No: 05.DA.50
Locality:

Notes:

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