Oct 21 2013
Pyrite is an iron sulfide mineral named from the Greek word for 'fire', as it emits sparks when hit with other metals or minerals.
Properties of Pyrite
The following are the key properties of Pyrite:
- Cell Data
- Space Group: Pa3
- a = 5.4179(11)
- Z = 4
- Crystal Data
- Cubic
- Point Group: 2/m 3
- Typically cubic, pyritohedral, octahedral, and combinations of these and other forms, to 25 cm or more. Striated conforming to pyritohedral symmetry; may be elongated to acicular. Commonly granular, globular, framboidal, stalactitic.
- Twinning: Twin axis [001] and twin plane {011}, penetration and contact twins
- X-ray Powder Pattern: 1.6332 (100), 2.7088 (85), 2.4281 (65), 2.2118 (50), 1.9155 (40), 3.128 (35), 1.4479 (25)
- Chemical Composition
| Elements |
Content 1 |
Content 2 |
Content 3 |
Content 4 |
| Fe |
46.49 |
29.30 |
33.32 |
46.55 |
| Ni |
- |
16.69 |
0.19 |
- |
| Co |
- |
trace |
13.90 |
- |
| S |
53.49 |
53.40 |
52.45 |
53.45 |
| Total |
99.98 |
99.39 |
99.86 |
100.00 |
- Optical Properties
- Estimated Properties
| Electron density |
Bulk density (electron density)=4.84 g/cm3
note: Specific gravity of Pyrite =5.01 g/cm3 |
| Photoelectric |
PEPyrite = 16.89 barns/electron
U= PEPyrite x ρElectron density= 81.83 barns/cm3 |
| Fermion index |
Fermion index = 0.01
Boson index = 0.99 |
| Radioactivity |
Pyrite is not radioactive |
How to Identify Pyrite
Pyrite has a pale brass yellow color with metallic luster, greenish black streak and opaque characteristics. It is non-fluorescent and magnetic after heating. Its fractures are characterized by smooth curved surfaces.
The average density of pyrite is 5.01 g/cm3, and its hardness is 6.5. The minerals forms stalagmites or stalactites shaped crystals with parallel lines on crystal surface.
Global Distribution
Pyrite is distributed in the following places:
- Rio Marina, on Elba, and at Traversella, Piedmont, Italy
- Ambasaguas and Navajun, Logroño Province, Spain
- Aktchitao, Kazakhstan
- Ibex mine, Leadville, Lake Co., Colorado
- Sparta, Randolph Co
- Santo Niño mine, near Duquesne, Santa Cruz Co., Arizona
- French Creek mines, Chester Co., Pennsylvania
- Carleton talc mine, Chester, Windsor Co., Vermont
- Butte, Silver Bow Co., Montana
- Spruce claim, King Co., Washington
- Buick mine, Bixby, Iron Co., Missouri
- Quiruvilca mine, La Libertad and Huanzala, Huanaco.
Occurrence of Pyrite and Useful Mineral Association
Pyrite occurs in hydrothermal veins as an accessory mineral in igneous rocks, magmatic segregations and as very large bodies. It also occurs in metamorphic rocks, sedimentary rocks as diagenetic replacements, contact metamorphic deposits and pegmatites.
It is closely associated with calcite, barite, quartz, fluorite, hematite, chalcopyrite, arsenopyrite, sphalerite, galena, marcasite and pyrrhotite.
References