Editorial Feature

Voglite - Occurrence, Properties, and Distribution

May 29 2014

Voglite was first discovered in the Elias mine, near Joachimstal in Bohemia, Czech Republic, in 1853. It is a secondary mineral, formed from the alteration of Uraninite.

It was named after Josef Florian Vogl, an Austrian mining official who first discovered it.

Properties of Voglite

The following are the key properties of Voglite:

Cell Data
- Space Group: P21/m or P21 (probable)
- a = 25.97–26.416
- b = 23.702–24.50
- c = 10.655–10.70
- β = 103.63°-104.02°
- Z = 16

Crystal Data
- Monoclinic
- Point Group: 2/m or 2
- As rhombic tabular to scaly crystals, to 0.5mm, in parallel stacked aggregates and coatings
- Twinning: Lamellar, with extinction angles up to 30°
- X-ray Powder Pattern: 12.6 (100), 8.70 (100), 9.65 (80), 7.10 (60), 4.32 (50), 6.13 (40), 4.65 (30)

Chemical Composition

Elements	Content 1	Content 2
UO₃	37.54	-
UO₂	37.0	-
CO₂	26.41	23.11
CaO	14.09	14.72
H₂O	13.9	14.19
CuO	8.40	10.44
Total	99.8	100.00

Optical Properties
- Optical Class: Biaxial (+)
- Pleochroism: X = deep blue to blue-green; Y = deep bluish-green to bluish-green; Z = pale yellow to yellow
- Orientation: X = b; Z ^ c = 33°–36°
- Dispersion: r < v, very strong
- α = 1.513–1.544
- β = 1.525–1.547
- γ = 1.542–1.564
- 2V(meas.) = 60°

Estimated Properties

Electron density	Bulk density (electron density) = 2.87 g/cm³ note: Specific gravity of Voglite = 3.06 g/cm³
Photoelectric	PE_Voglite = 761.60 barns/electron U = PEVoglite x ?Electron density = 2184.10 barns/cm³
Fermion index	Fermion index = 0.0032 Boson index = 0.9967
Radioactivity	Voglite is not radioactive

How to Identify Voglite

Voglite can be identified from its bright, grass-green and emerald-green colors. It has a transparent to translucent appearance, with a pearly luster, perfect cleavage, and pale green streak. It is non-fluorescent and has scaly morphology.

The density of voglite is 2.8 g/cm³.