May 15 2013
Nuffieldite is an orthorhombic-dipyramidal pale creamy white mineral containing sulfur, lead, copper and bismuth. The mineral was found in Lime Creek stock, Alice Arm, BC, Canada in 1968. It was named after Edward W. Nuffield, Canadian mineralogist.
Properties of Nuffieldite
The following are the key properties of Nuffieldite:
- Cell Data
- Space Group: Pbnm
- a = 14.387(7)
- b = 21.011(15)
- c = 4.046(6)
- Z = 4
- Crystal Data
- Orthorhombic
- Point Group: 2/m 2/m 2/m
- As prismatic to acicular crystals, deeply striated and channelled k [001]; as bundles of these unterminated crystals, to 3 mm
- X-ray Powder Pattern: 3.66 (100), 3.54 (100), 4.00 (90), 3.16 (80), 2.54 (70), 1.871 (60), 1.349 (40)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
Content 3 |
| Bi |
42.00 |
37.97 |
42.28 |
| Pb |
34.12 |
36.63 |
33.77 |
| S |
17.52 |
16.51 |
17.10 |
| Cu |
5.81 |
6.41 |
5.52 |
| Sb |
1.33 |
2.15 |
2.18 |
| Total |
100.78 |
99.67 |
100.85 |
- Optical Properties
- Anisotropism: Very weak, from bluish gray to grayish red
- Estimated Properties
| Electron density |
Bulk density (electron density)=5.84 g/cm3
note: Specific gravity of Nuffieldite =7.01 g/cm3 |
| Photoelectric |
PENuffieldite = 1481.29 barns/electron
U= PENuffieldite x ρElectron density= 8652.83 barns/cm3 |
| Fermion index |
Fermion index = 0.08
Boson index = 0.92 |
Radioactivity
|
Nuffieldite is not radioactive
|
How to Identify Nuffieldite
Nuffieldite occurs in reddish brown, grayish green, steel gray or gray color. It is opaque, and has a perfect cleavage, metallic luster and grayish black streak. Its fractures are brittle producing uneven fragments. It can be formed as needle-like crystals or prismatic crystals. The density of nuffieldite is 7.01 g/cm3 and its hardness ranges from 3.5 to 4.
Global Distribution
Nuffieldite is distributed in the following places:
- Patsy Creek, immediately south of the Lime Creek molybdenum deposit, Kitsault, near Alice Arm, British Columbia
- Izok Lake, Northwest Territories, Canada
- Alaska mine, Poughkeepsie Gulch, San Juan Co., Colorado, USA
- Secu Valley, Baia Bor¸a district, Romania
- Spissko-Gemerske Ore Mountains, eastern Slovakia
- Les Houches, Haute-Savoie, France
- Maleevskoe, Rudnyi Altai, Russia
- Akchatau, Kara Oba, and in the Ichkeul’nes skarn copper deposit, Kazakhstan.
Occurrence of Nuffieldite and Useful Mineral Association
Nuffieldite occurs in vugs in a small quartz vein in the Lime Creek stock. It is closely associated with minerals such as sphalerite, chalcopyrite, tetrahedrite, galena, neyite, sphalerite, galena, pyrite, aikinite, cosalite and molybdenite.
References