Oct 11 2013
Bariandite has been named after Dr.Pierre Bariand, Curator of Mineralogy at the University of Paris, France. It belongs to the Straczekite mineral group.
Properties of Bariandite
The following are the key properties of bariandite:
- Cell Data
- Space Group : Cc or C2/c
- a=11.70(3)
- b=3.63(1)
- c=20.06(5)
- β=101°30(20)’
- Z=2
- Crystal Data
- Monoclinic, pseudo-orthorhombic
- Point Group: m or 2/m
- Crystals elongated || [010], forming fibers, platy on {001}, to 3 mm; in sheeted aggregates of parallel fibers, such layers sometimes stacked
- X-ray Powder Pattern: 14.20 (FFF), 3.480 (F), 3.430 (F), 5.72 (mF), 2.852 (mF), 1.939 (mF), 1.827 (mF)
- Chemical Composition
| Elements |
Content 1 |
| V2O5 |
63.26 |
| V2O4 |
14.19 |
| Al2O3 |
3.75 |
| Fe2O3 |
0.17 |
| H2O |
18.11 |
| Total |
[99.48] |
- Optical Properties
- Nearly Opaque
- Color: black to dark green; in reflected light exhibits green total internal reflections
- Optical Class: Biaxial (-)
- Pleochroism: greenish brown || [010]; bottle-green ⊥ [010] in
- transmitted light; strong in brownish gray under re?ected light
- n => 1.85
- Estimated Properties
| Electron density |
Bulk density (electron density) = 2.43 g/cm3
note: Specific gravity of bariandite = 2.49 g/cm3 |
| Photoelectric |
PEBariandite = 8.59 barns/electron
U=PEBariandite x ρ electron density= 20.87 barns/cm3 |
| Fermion index |
Fermion index = 0.0013735916
Boson index = 0.99862640684 |
| Radioactivity |
Bariandite is not radioactive |
How to Identify Bariandite
The color of bariandite varies from black to dark green. It shows green total internal reflection in reflected light.
Global Distribution
Bariandite is found in the Mounana uranium mine, Franceville, Gabon and at Minasragra in Peru.
Occurrence of Bariandite and Useful Mineral Association
Bariandite occurs in the oxidation zone of a uranium mineral deposit and in the oxidation zone of a vanadium deposit. It is associated with duttonite, lenoblite, gypsum and roscoelite.
References