Oct 21 2013
Raspite, a member of the Scheelite group, was first discovered in 1897 at Broken Hill, New South Wales, Australia. The mineral was named after Charles Rasp, German-Australian prospector, discoverer of the Broken Hill ore deposit.
Properties of Raspite
The following are the key properties of Raspite:
- Cell Data
- Space Group: P21/a
- a = 13.555(11)
- b = 4.976(2)
- c = 5.561(3)
- β = 107.63(7)°
- Z = 4
- Crystal Data
- Monoclinic
- Point Group: 2/m
- Crystals are typically flattened on {100}, elongated along [010] or [100], may be flat tabular on {101}; prominent forms are {100}, {011}, {001}, {010}, several others modifying, to 1.3 cm. Twinning: On {100}, common as interpenetration twins; also on {102}
- X-ray Powder Pattern: 3.224 (100), 2.760 (60), 3.619 (55), 2.705 (55), 1.812 (25), 3.593 (20), 3.478 (20)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
| PbO |
49.06 |
49.05 |
| WO3 |
48.32 |
50.95 |
| rem. |
1.43 |
- |
| Total |
98.81 |
100.00 |
- Optical Properties
- Optical Class: Biaxial (+)
- Orientation: Y = b; Z ^ c ˜30°
- α = 2.27(2)
- β = 2.27(2)
- γ = 2.30(2)
- 2V(meas.) = ?0°
- Estimated Properties
| Electron density |
Bulk density (electron density)=6.99 g/cm3
note: Specific gravity of Raspite =8.47 g/cm3 |
| Photoelectric |
PERaspite = 1373.52 barns/electron
U= PERaspite x ρElectron density= 9607.12 barns/cm3 |
| Fermion index |
Fermion index = 0.15
Boson index = 0.85 |
| Radioactivity |
Raspite is not radioactive |
How to Identify Raspite
Raspite can be identified by light yellow, yellow gray or yellow brown color variations. It has perfect cleavage, a yellow white streak and adamantine luster. The hardness of raspite ranges from 2.5 to 3, and its density is 8.47 g/cm3.
Global Distribution
Raspite is distributed in the following places:
- Proprietary mine, Broken Hill, and the Cordillera mine, near Tuena, New South Wales, Australia
- Otani mine, Kyoto Prefecture, Japan
- Kramat Pulai mine, Kinta district, Perak, Malaysia
- Sumidoro gold placers, Municipio do Mariana, Minas Gerais, Brazil
- Gifurwe, Rwanda
- Clara mine, near Oberwolfach, Black Forest, Germany
Occurrence of Raspite and Useful Mineral Association
Raspite occurs as an uncommon secondary mineral formed in the oxidized zone of tungsten-bearing hydrothermal base metal deposits. Ferritungstite, cuprotungstite, alumotungstite, yttrotungstite and stolzite are closely associated with raspite.
References