Tengchongite Mineral Data

General Tengchongite Information

Chemical Formula:

CaU++++++6Mo++++++2O25•12(H2O)

Composition:

Molecular Weight = 2,276.30 gm

Calcium 1.76 % Ca 2.46 % CaO

Uranium 62.74 % U 75.39 % UO₃

Molybdenum 8.43 % Mo 12.65 % MoO₃

Hydrogen 1.06 % H 9.50 % H₂O

Oxygen 26.01 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

CaU₆Mo₂O₂₅•12(H₂O)

Environment:

In the oxidized portions of a uranium deposit in migmatite and gneiss.

IMA Status:

Approved IMA 1986

Locality:

Tongbiguan village, Tengchong Co., Yunnan Province, China. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Name Pronunciation:

Tengchongite + Pronunciation

Tengchongite Crystallography

Axial Ratios:

a:b:c =1.1972:1:1.3582

Cell Dimensions:

a = 15.616, b = 13.043, c = 17.716, Z = 4; V = 3,608.39 Den(Calc)= 4.19

Crystal System:

Orthorhombic - Disphenoidal H-M Symbol (2 2 2) Space Group: A2122

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

By Intensity(I/I_o): 8.84(1), 3.17(0.8), 3.38(0.7),

Physical Properties of Tengchongite

Color:

Yellow.

Density:

4.25

Diaphaneity:

Transparent to Translucent

Hardness:

2-2.5 - Gypsum-Finger Nail

Luster:

Vitreous (Glassy)

Streak:

light yellow

Optical Properties of Tengchongite

Gladstone-Dale:

CI meas= -0.096 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.111 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1738,KPDmeas= 0.1714,KC= 0.1564
Ncalc = 1.66

Optical Data:

Biaxial (-), a=1.663, b=1.76, g=1.762, bire=0.0990, 2V(Calc)=14, 2V(Meas)=16.

Calculated Properties of Tengchongite

Electron Density:

Bulk Density (Electron Density)=3.64 gm/cc
note: Specific Gravity of Tengchongite =4.25 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Tengchongite=1,675.23 barns/electron
U=PE_Tengchongite x r_electron=6,105.40 barns/cc.

Radioactivity:

GRapi = 4,586,016.19 (Gamma Ray American Petroleum Institute Units)
Concentration of Tengchongite per GRapi unit = 218.05 (PPB)

Tengchongite 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) 6.63 ± 1.66 grams of pure Tengchongite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 663.25 ±165.81 grams of pure Tengchongite .

**Estimated Radioactivity from Tengchongite** - 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 / 7.66 cm	112,306,403	3.04E-03	4,586,016.19	1,507.73
100 gm / 3.56 cm	11,230,640	3.04E-04	458,601.62	150.77
10 gm / 1.65 cm	1,123,064	3.04E-05	45,860.16	15.08
1 gm / 7.66 mm	112,306	3.04E-06	4,586.02	1.51
0.1 gm / 3.56 mm	11,231	3.04E-07	458.60	0.15
0.01 gm / 1.65 mm	1,123	3.04E-08	45.86	0.02
0.001 gm / 0.77 mm	112	3.04E-09	4.59	0.00

Weight of pure Tengchongite in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.25 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

Tengchongite Classification

Dana Class:

49.03.01.02 (49)Basic and Hydrated Molybdates and Tungstates

(49.03)(Hydrated, containing Hydroxyl or Halogen)

(49.03.01)Calcurmolite Group

49.03.01.01 Calcurmolite Ca(UO2)3(MoO4)3(OH)2•11(H2O) Unk Mono

49.03.01.02 Tengchongite CaU6Mo2O25•12(H2O) A2122 2 2 2

Strunz Class:

07.HB.20 07 - SULFATES (SELENATES, TELLURATES)

07.H - Uranium and Uranyl Molybdates and Wolframates

07.HB -With U6+

07.HB.20 Tengchongite CaU6Mo2O25•12(H2O) A2122 2 2 2

Other Tengchongite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Am.Min.,Vol.73,p195,1988) OPTIC PROP.(Am.Min.,Vol.73,p195,1988)

See Also:

Links to other databases for Tengchongite :
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
15 - Uranium Minerals

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Tengchongite

CaU++++++6Mo++++++2O25•12(H2O)
Dana No: 49.03.01.02 Strunz No: 07.HB.20
Locality:

Notes:

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