Sep 26 2013
Brendelite was named after Christian Friedrich Brendel (1776–1861), an expert in mining equipment, in Neustadtel-Schneeberg, Germany.
Properties of Brendelite
The following are the key properties of brendelite:
- Cell Data
- Space group: C2/m
- a = 12.278(2)
- b = 3.815(1)
- c = 6.899(1)
- β = 111.14(1)°
- Z = 2
- Crystal Data
- Monoclinic
- Point group: 2/m
- Crystals are tabular {201}, showing also {100}, {010}, {001}, to 0.3 mm, in aggregates
- X-ray powder pattern: 3.011 (100), 3.372 (77), 2.750 (62), 5.726 (54), 3.217 (46), 3.322 (37), 2.863 (34)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
| Bi2O3 |
47.10 |
56.12 |
| PbO |
26.08 |
18.12 |
| P2O5 |
10.71 |
10.98 |
| Fe2O3 |
9.44 |
6.32 |
| FeO |
3.12 |
5.58 |
| H2O |
[1.46] |
[1.46] |
| As2O5 |
0.32 |
0.20 |
| V2O5 |
0.24 |
0.55 |
| Total |
[98.47] |
[99.33] |
- Optical Properties
- Optical class: Biaxial (-)
- Pleochroism: Strong; X = pale brown to brown; Y = Z = dark brown to opaque
- Orientation: Z = b; Y ≃a
- α = [2.06]; β = [2.15]; γ = [2.19]
- 2V(meas.) =70.5°
- Estimated Properties
| Electron density |
Bulk density (electron density) = 5.83 g/cm3
note: Specific gravity of brendelite = 6.83 g/cm3 |
| Photoelectric |
PEBrendelite = 1,255.52 barns/electron
U=PEBrendelite x ρ electron density= 7,324.08 barns/cm3 |
| Fermion index |
Fermion index = 0.05
Boson index = 0.95 |
| Radioactivity |
Brendelite is not radioactive |
How to Identify Brendelite
Brendelite can be identified in the field by its color variations of black and dark brown. Its opaque to translucent form has no cleavage. This mineral has a vitreous - adamantine luster with light brown streak. The density of brendelite is 6.83 g/cm3 with a hardness of 4.5 - between fluorite and apatite.
Global Distribution
Brendelite is mainly distributed in the Guldener Falk mine, near Schneeberg, Saxony, Germany.
Occurrence of Brendelite and Useful Mineral Association
Brendelite occurs in a very rare secondary mineral found on the dumps of a Bi–Co–Ni–Ag deposit. It is often associated with minerals such as eulytite, bismutite, and bismutoferrite.
References