May 29 2014
Walfordite was first discovered in the Tambo mine, Chile, in 1999. It is a mineral species of tellurite.
It was named after Phillip Walford, Vice-President and Chief Geologist of LAC Minerals, who first noticed the mineral.
Properties of Walfordite
The following are the key properties of Walfordite:
- Cell Data
- Space Group: Ia3
- a = 11.011(5)
- Z = 8
- Crystal Data
- Cubic
- Point Group: 2/m 3
- Crystals are cubic {100}, may be modified by minor {111}, to 0.2mm
- X-ray Powder Pattern: 3.175 (100), 1.658 (45), 1.944 (44), 2.749 (37), 4.486 (29), 2.943 (23), 2.592 (22)
- Chemical Composition
| Elements |
Content 1 |
| TeO2 |
81.74 |
| TeO3 |
8.67 |
| Fe2O3 |
8.30 |
| TiO2 |
1.11 |
| MgO |
0.38 |
| Total |
100.20 |
- Optical Properties
- Optical Class: Isotropic
- n = [2.23] (by the rule of Gladstone and Dale)
- Estimated Properties
| Electron density |
Bulk density (electron density) = 2.53 g/cm3
note: Specific gravity of Walfordite = 2.94 g/cm3 |
| Photoelectric |
PEWalfordite = 259.14 barns/electron
U = PEWalfordite x ρElectron density = 656.88 barns/cm3 |
| Fermion index |
Fermion index = 0.05
Boson index = 0.95 |
Radioactivity
|
Walfordite is not radioactive
|
How to Identify Walfordite
Walfordite is an orange colored mineral, having translucent appearance, adamantine luster, and orange-yellow streak. Its fractures are brittle, usually exhibited by most of the non-metallic minerals and glasses. The crystals of walfordite are microscopic in nature.
Global Distribution
Walfordite is largely distributed in the Wendy open pit, El Indio-Tambo district, east of La Serena, Coquimbo, Chile.
Occurrence of Walfordite and Useful Mineral Association
Walfordite occurs very rarely in the brecciated oxidized zone of a tellurium-bearing hydrothermal gold deposit.
It is closely associated with pyrite, jarosite, emmonsite, gold, rodalquilarite, and alunite.
References