Thorianite

Thorianite
IMA-GP
Thorium 5.1.1.2
(Dana Classification Number)
(Images) 4/D.31-50
(Strunz ID)

Property Data Remarks
Named for: Its Thorium content
Alternate
Name(s):
alpha-Thorianite

beta-Thorianite

gamma-Thorianite

Mineral Class: Oxides & Hydroxides -
- Badleyite - Uraninite series
Chemical
Formula: ThO₂
Chemical
Composition:

Oxygen: (O) 12.12%
Thorium: (Th) 87.88%

by weight
Molecular
Weight: 264.04 daltons (amu)
Specific
Radioactivity:
(All radiation is for a 1 gram, fully aged specimen)

Specific Activity Dose Rate
Becquerels Curies milliRems/hour microSieverts/hour
3.9371 × 10⁰⁴ 1.06 × 10^-06 0.49 49.49

Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)

Crystalography:

System: Isometric - Hexoctahedral
Cell Dimensions: a = 5.595, Z = 4; V = 175.15 Den(Calc) = 10.01
H-M Symbol: 4/m -3 2/m
Space Group: Fm3m
X Ray Diffraction: By Intensity(I/Io): 3.234(1) 1.689(0.64) 1.98(0.58)

Thorianite
Crystal
Habit:
Pseudo Hexagonal - Crystals show a hexagonal outline.

Granular - Generally occurs as anhedral to subhedral crystals in matrix.

Cleavage:

[001] Imperfect
[010] Imperfect
[100] Imperfect

Fracture: Brittle - Conchoidal
Moh's
Hardness: 6 - 6.5 - 7
Density: 10 grams/cm³
Color: Brownish black, Green, Green black, Gray green, Yellow or Orange
Streak: Black to brownish white
Luster: Metallic
Diaphaneity: Opague
Pleochroism:

(x):
(y:)
(z:)

Ultra Violet
Fluorescence:

Long Wave: None
Short Wave: None

Magnetism: Non-magnetic
Occurance:
Pegmatites.

Alluvial deposits.

Contact modified limestones

Associated
Minerals:
Aegirine, Albite, Allanite-(Ce), Analcime, 'Apatite', Barite, Biotite, Calcite, 'Chabazite', Chalcopyrite, Chondrodite, Diopside, Dolomite, Epidote, Eudialyte, Fluorapatite, Fluorite, Forsterite, Galena, Goethite, Graphite, Ilmenite, Magnetite, Microcline, Molybdenite, Monazite-(Ce), Muscovite, Natrolite, Nepheline, Orthoclase, Phlogopite, Prehnite, Pyrite, Pyrochlore, Pyrrhotite, Quartz, 'Scapolite', Sphalerite, Thorite, Titanite, Xenotime-(Y), Zircon

Mineral - > 62% of sites
Mineral - > 41% of sites
Mineral - > 21% of sites
Minerals - Uranium & Thorium
mineral links
These are minerals known to be found with Thorianite
Locations:
Very rare

Thorianite Locations

Notes:
Strongly radioactive a- and b-particles, g-rays.

Thorianite is at one end of a spectrum of minerals, with Uraninite at the opposite end, varrying in the amount of uranium and thorium that they contain.