Threadgoldite Mineral Data

Threadgoldite Mineral Data +

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General Threadgoldite Information

Chemical Formula:

Al(UO2)2(PO4)2(OH)·8(H2O)

Composition:

Molecular Weight = 918.11 gm

Uranium 51.85 % U 58.82 % UO₂

Aluminum 2.94 % Al 5.55 % Al₂O₃

Phosphorus 6.75 % P 15.46 % P₂O₅

Hydrogen 1.87 % H 16.68 % H₂O

Oxygen 36.60 % O

______ ______

100.00 % 96.51 % = TOTAL OXIDE

Empirical Formula:

Al(UO₂)₂(PO₄)₂(OH)·8(H₂O)

Environment:

The P analog of metavanuralite.

IMA Status:

Approved IMA 1979

Locality:

Kobokobo, Kivu, Zaire. Link to MinDat.org Location Data.

Name Origin:

Named for Ian M. Threadgold (1929-), University of Sydney, NSW, Australia.

Synonym:

ICSD 31265

PDF 33-39

Threadgoldite Image

Images:

Threadgoldite

Comments: Beige threadgoldite filling cracks in, and coating, black uraninite. Schumacher Collection.
Location: Kobokobo Pegmatite, Lusungu River District, Kivu, Congo (Za?re). Scale: Picture size 5 mm.
© Paul M. Schumacher

Threadgoldite Crystallography

Axial Ratios:

a:b:c =2.0558:1:2.005

Cell Dimensions:

a = 20.25, b = 9.85, c = 19.75, Z = 8; beta = 111.4° V = 3,667.79 Den(Calc)= 3.33

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: C 2/c

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

By Intensity(I/I_o): 9.43(1), 3.474(0.8), 3.366(0.6),

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

Khosrawan-Sazedj F , Tschermaks Mineralogische und Petrographische Mitteilungen , 30 (1982) p.111-115, On the space group of threadgoldite

Physical Properties of Threadgoldite

Cleavage:

[???] Perfect

Color:

Greenish yellow.

Density:

3.4

Diaphaniety:

Translucent

Habit:

Micaceous - Platy texture with "flexible" plates.

Habit:

Tabular - Form dimensions are thin in one direction.

Hardness:

2-3 - Gypsum-Calcite

Luminescence:

Fluorescent, Short UV=pale green, Long UV=green.

Streak:

yellow white

Optical Properties of Threadgoldite

Gladstone-Dale:

CI meas= -0.101 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.124 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1746,KPDmeas= 0.171,KC= 0.1553

Optical Data:

Biaxial (-), a=1.573, b=1.583, g=1.588, bire=0.0150, 2V(Calc)=70, 2V(Meas)=70.

Pleochroism (x):

colorless.

Pleochroism (z):

pale yellow.

Calculated Properties of Threadgoldite

Electron Density:

r_electron=3.05 gm/cc
note: r_{Threadgoldite}=3.40 gm/cc.

Fermion Index

Fermion Index = 0.00391
Boson Index = 0.99609

Photoelectric:

PE_{Threadgoldite}=1,311.26 barns/electron
U=PE_{Threadgoldite} x r_electron=4,001.28 barns/cc.

Radioactivity:

GRapi = 3,966,721.39 (Gamma Ray American Petroleum Institute Units)

Threadgoldite is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.

Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 10 cm box) 7.67 ± 1.92 grams of pure Threadgoldite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 766.80 ±191.70 grams of pure Threadgoldite .

**Estimated Radioactivity from Threadgoldite** - very strong
Specimen Size Weight/Volume (Sphere) *	Calculated Activity Bequerols (Bq)	Calculated Activity Curies (Ci)	Estimated Activity GR(api)	Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 8.25 cm	92,815,026	2.51E-03	3,966,721.39	1,304.13
100 gm / 3.83 cm	9,281,503	2.51E-04	396,672.14	130.41
10 gm / 1.78 cm	928,150	2.51E-05	39,667.21	13.04
1 gm / 8.25 mm	92,815	2.51E-06	3,966.72	1.30
0.1 gm / 3.83 mm	9,282	2.51E-07	396.67	0.13
0.01 gm / 1.78 mm	928	2.51E-08	39.67	0.01
0.001 gm / 0.83 mm	93	2.51E-09	3.97	0.00

Weight of pure Threadgoldite in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.40 gm/cc.*
Goverment Estimate of Average Annual Exposure ( 360 mRem) **
Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem

Threadgoldite Classification

Dana Class:

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

(42.11)where (AB)4 (XO4)3 Zq · x(H2O)

(42.11.13)Dana Group

42.11.13.1 Vanuralite Al(UO2)2(VO4)2(OH)·11(H2O) A2/a 2/m

42.11.13.2 Metavanuralite Al(UO2)2(VO4)2(OH)·8(H2O) P 1or P1 Tri

42.11.13.3 Threadgoldite Al(UO2)2(PO4)2(OH)·8(H2O) C 2/c 2/m

Strunz Class:

VII/E.05-40 VII - Phosphates, Arsenates and Vanadates

VII/E - Uranylphosphates and uranylvanadates with [UO2]2+ - [PO4 | AsO4]3- and [UO2]2+ - [V2O8]6-

VII/E.05 - Ranunculite - Moreauite series

VII/E.05-10 Ranunculite HAl(UO2)(PO4)(OH)3·4(H2O) Unk (pseudo ORTH) Mono

VII/E.05-20 Triangulite Al3(UO2)4(PO4)4(OH)5·5(H2O) P1,P 1 Tri

VII/E.05-30 Upalite Al(UO2)3(PO4)2O(OH)·7(H2O) P 2₁/a 2/m

VII/E.05-40 Threadgoldite Al(UO2)2(PO4)2(OH)·8(H2O) C 2/c 2/m

VII/E.05-50 Furongite Al2(UO2)(PO4)3(OH)2·8(H2O) P1 1

VII/E.05-60 Moreauite Al3(UO2)(PO4)3(OH)2·13(H2O) P 2₁/c 2/m

Other Threadgoldite Information

References:

NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Threadgoldite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas 12 - Uranium Minerals 13 - WWW-MINCRYST 14 -École des Mines de Paris

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

Threadgoldite

Al(UO2)2(PO4)2(OH)·8(H2O)
Dana No: 42.11.13.3 Strunz No: VII/E.05-40
Locality:

Notes: