Coffinite Mineral Data

Coffinite Mineral Data

[Register] [Auction Rules] [Current Listing] [About Us] [Site Map]
e-Rocks.com, auction and sales venue for all rock and mineral enthusiasts
Our mission is to provide an online centre for Buyers and Sellers with reliable service and support
Brought to you by Thames Valley Minerals

General Coffinite Information

Chemical Formula:

U(SiO4)1-x(OH)4x

Composition:

Molecular Weight = 327.71 gm

Uranium 72.63 % U 82.40 % UO₂

Silicon 7.71 % Si 16.50 % SiO₂

Hydrogen 0.12 % H 1.10 % H₂O

Oxygen 19.53 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

U(SiO₄)_0.9(OH)_0.4

IMA Status:

Valid Species (Pre-IMA) 1956

Locality:

Link to MinDat.org Location Data.

Synonym:

ICSD 15484

PDF 11-420

Coffinite Image

Images:

Coffinite

Comments: Black, interstitial coffinite cementing a sub-angular quartzose sandstone. Schumacher Collection.
Location: Temple Mountain, San Rafael District (San Rafael Swell), Emery Co., Utah, USA. Scale: Picture size 5 mm.
© Paul M. Schumacher

Coffinite Crystallography

Axial Ratios:

a:c = 1:0.90187

Cell Dimensions:

a = 6.93, c = 6.25, Z = 3; V = 300.16 Den(Calc)= 5.44

Crystal System:

Tetragonal - Ditetragonal DipyramidalH-M Symbol (4/m 2/m 2/m) Space Group: I 4₁/amd

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

By Intensity(I/I_o): 3.47(1), 4.66(1), 2.64(0.7),

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

Fuchs L H , Gebert E , American Mineralogist , 43 (1958) p.243-248, X-ray studies of synthetic coffinite, thorite and uranothorites

Physical Properties of Coffinite

Cleavage:

None

Color:

Black, Pale brown, Dark brown.

Density:

5.1

Diaphaniety:

Subtranslucent to Opaque

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Hardness:

5-6 - Between Apatite and Orthoclase

Luster:

Subadamantine

Streak:

grayish black

Optical Properties of Coffinite

Gladstone-Dale:

CI meas= -0.205 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.129 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.136,KPDmeas= 0.1451,KC= 0.1205

Optical Data:

Uniaxial (+/-), a=1.73-1.75, b=1.73-1.75, bire=0.0000.

Calculated Properties of Coffinite

Electron Density:

r_electron=4.55 gm/cc
note: r_Coffinite=5.44 gm/cc.

Fermion Index

Fermion Index = 0.00892
Boson Index = 0.99108

Photoelectric:

PE_Coffinite=1,971.22 barns/electron
U=PE_Coffinite x r_electron=8,965.99 barns/cc.

Radioactivity:

GRapi = 5,176,585.31 (Gamma Ray American Petroleum Institute Units)

Coffinite 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) 5.88 ± 1.47 grams of pure Coffinite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 587.58 ±146.90 grams of pure Coffinite .

**Estimated Radioactivity from Coffinite** - 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 / 7.05 cm	130,016,203	3.51E-03	5,176,585.31	1,701.89
100 gm / 3.27 cm	13,001,620	3.51E-04	517,658.53	170.19
10 gm / 1.52 cm	1,300,162	3.51E-05	51,765.85	17.02
1 gm / 7.05 mm	130,016	3.51E-06	5,176.59	1.70
0.1 gm / 3.27 mm	13,002	3.51E-07	517.66	0.17
0.01 gm / 1.52 mm	1,300	3.51E-08	51.77	0.02
0.001 gm / 0.71 mm	130	3.51E-09	5.18	0.00

Weight of pure Coffinite in grams (gm) and Calculated Diameter of a Sphere with a Density of 5.44 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

Coffinite Classification

Dana Class:

51.5.2.4 (51)Nesosilicate Insular SiO4 Groups Only

(51.5)with cations in >[6] coordination

(51.5.2)Zircon group

51.5.2.1 Zircon ZrSiO4 I 4₁/amd 4/m 2/m 2/m

51.5.2.2 Hafnon HfSiO4 I 4₁/amd 4/m 2/m 2/m

51.5.2.3 Thorite ThSiO4 I 4₁/amd 4/m 2/m 2/m

51.5.2.4 Coffinite U(SiO4)1-x(OH)4x I 4₁/amd 4/m 2/m 2/m

51.5.2.5 Thorogummite Th(SiO4)1-x(OH)4x I 4₁/amd 4/m 2/m 2/m

Strunz Class:

VIII/A.09-40 VIII - Silicates

VIII/A - Nesosilicates with [SiO4]4-groups, cations of octahedral and cubic orientation [8+6]

VIII/A.09 - Zircon - Thorogummite series

VIII/A.09-05 Reidite! ZrSiO4 I 4₁/a 4/m

VIII/A.09-10 Zircon ZrSiO4 I 4₁/amd 4/m 2/m 2/m

VIII/A.09-20 Hafnon HfSiO4 I 4₁/amd 4/m 2/m 2/m

VIII/A.09-30 Thorite ThSiO4 I 4₁/amd 4/m 2/m 2/m

VIII/A.09-40 Coffinite U(SiO4)1-x(OH)4x I 4₁/amd 4/m 2/m 2/m

VIII/A.09-50 Thorogummite Th(SiO4)1-x(OH)4x I 4₁/amd 4/m 2/m 2/m

Other Coffinite Information

References:

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

Search for Coffinite using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Coffinite :
AA Mineral Specimens
B and L Minerals
Crystal Vaults
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Coffinite Mineral Data :

Ask about Coffinite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

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

Coffinite

U(SiO4)1-x(OH)4x
Dana No: 51.5.2.4 Strunz No: VIII/A.09-40
Locality:

Notes: