Brabantite Mineral Data

General Brabantite Information

Chemical Formula:

CaTh(PO4)2

Composition:

Molecular Weight = 462.06 gm

Calcium 8.67 % Ca 12.14 % CaO

Thorium 50.22 % Th 57.14 % ThO₂

Phosphorus 13.41 % P 30.72 % P₂O₅

Oxygen 27.70 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

CaTh(PO₄)₂

Environment:

In a zoned granite pegmatite. The name brabantite (1980) has been discredited, cheralite having priority as name for members dominated by CaTh(PO4)2.

IMA Status:

Discredited IMA 2006

Locality:

In the Van der Made pegmatite, Brabant Farm, west of Itiro, Karibib district, Namibia. Link to MinDat.org Location Data.

Name Origin:

For the Brabant Farm, Namibia, location of the pegmatite where the mineral was first found.

Name Pronunciation:

Brabantite + Pronunciation

Synonym:

Lingaitukuang

Brabantite Image

Images:

Brabantite

Comments: Altering micro grain of brabantite.
Location: Kuttakuzhi, near Trivandrum, Travancore, Kerala, India. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Brabantite Crystallography

Axial Ratios:

a:b:c =0.9701:1:0.9299

Cell Dimensions:

a = 6.726, b = 6.933, c = 6.447, Z = 2; beta = 103.883° V = 291.85 Den(Calc)= 5.26

Crystal System:

Monoclinic - Sphenoidal H-M Symbol (2) Space Group: P 2₁

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

By Intensity(I/I_o): 3.06(1), 2.85(0.75), 3.26(0.7),

Physical Properties of Brabantite

Cleavage:

{100} Good, {001} Good

Color:

Gray brown, Reddish brown.

Density:

4.72

Diaphaneity:

Transparent to Translucent

Hardness:

5.5 - Knife Blade

Luster:

Vitreous - Resinous

Optical Properties of Brabantite

Gladstone-Dale:

CI meas= 0.127 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.217 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1388,KPDmeas= 0.1547,KC= 0.1771
Ncalc = 1.84 - 1.93

Optical Data:

Biaxial (?), b=1.73

Calculated Properties of Brabantite

Electron Density:

Bulk Density (Electron Density)=4.17 gm/cc
note: Specific Gravity of Brabantite =4.72 gm/cc.

Fermion Index:

Fermion Index = 0.0002505634
Boson Index = 0.9997494366

Photoelectric:

PE_Brabantite=1,198.21 barns/electron
U=PE_Brabantite x r_electron=4,993.89 barns/cc.

Radioactivity:

GRapi = 945,983.71 (Gamma Ray American Petroleum Institute Units)
Concentration of Brabantite per GRapi unit =1,057.10 (PPB)

Brabantite 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) 32.15 ± 8.04 grams of pure Brabantite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 3215.3 ±803.84 grams of pure Brabantite .

**Estimated Radioactivity from Brabantite** - 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 / 7.40 cm	22,497,800	6.08E-04	945,983.71	311.01
100 gm / 3.43 cm	2,249,780	6.08E-05	94,598.37	31.10
10 gm / 1.59 cm	224,978	6.08E-06	9,459.84	3.11
1 gm / 7.40 mm	22,498	6.08E-07	945.98	0.31
0.1 gm / 3.43 mm	2,250	6.08E-08	94.60	0.03
0.01 gm / 1.59 mm	225	6.08E-09	9.46	0.00
0.001 gm / 0.74 mm	22	6.08E-10	0.95	0.00

Weight of pure Brabantite in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.72 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

Brabantite Classification

Dana Class:

38.04.03.04 (38)Anhydrous Phosphates, etc

(38.04)A+ XO4

(38.04.03)Monazite Group (Monoclinic: P21/n)

38.04.03.01 Monazite-(Ce) (Ce,La,Nd,Th)PO4 P 2₁/n 2/m

38.04.03.02 Monazite-(La) (La,Ce,Nd)PO4 P 2₁/n 2/m

38.04.03.03 Cheralite-(Ce)? (Ce,Ca,Th)(P,Si)O4 P 2₁/n 2/m

38.04.03.04 Brabantite? CaTh(PO4)2 P 2₁ 2

38.04.03.05 Monazite-(Nd) (Nd,Ce,La)(P,Si)O4 P 2₁/n 2/m

38.04.03.06 Gasparite-(Ce) CeAsO4 P 2₁/n 2/m

38.04.03.07 Monazite-(Sm)! SmPO4 P 2₁/n 2/m

Strunz Class:

08.AD.50 08 - PHOSPHATES, ARSENATES, VANADATES

08.A - Phosphates, etc. without additional anions, without H2O

08.AD -With only large cations

08.AD.50 Brabantite? CaTh(PO4)2 P 2₁ 2

08.AD.50 Gasparite-(Ce) CeAsO4 P 2₁/n 2/m

08.AD.50 Monazite-(Ce) (Ce,La,Nd,Th)PO4 P 2₁/n 2/m

08.AD.50 Monazite-(La) (La,Ce,Nd)PO4 P 2₁/n 2/m

08.AD.50 Monazite-(Nd) (Nd,Ce,La)(P,Si)O4 P 2₁/n 2/m

08.AD.50 Rooseveltite BiAsO4 P 2/m 2/m

08.AD.50 Monazite-(Sm)! SmPO4 P 2₁/n 2/m

Other Brabantite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Brabantite :
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
16 - WWW-MINCRYST

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

Brabantite

CaTh(PO4)2
Dana No: 38.04.03.04 Strunz No: 08.AD.50
Locality:

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