Where it forms, where it's found
- Geological setting
Metamorphosed igneous rocks. Hornblende andesite.
- Type locality
- Buena Vista Iron Mine
- Mineral Basin Mining District
- Churchill County
- Nevada
- USA
39.9739°, -118.1683°
15recorded occurrences
Physical
Optical
- Tropism
- Isotropic
- Reflectance R%
- 16.64 (400), 16.44 (420), 16.28 (440), 16.21 (460), 16.18 (480), 16.18 (500), 16.23 (520), 16.3 (540), 16.38 (560), 16.46 (580), 16.54 (600), 16.67 (620), 16.83 (640), 17.03 (660), 17.26 (680), 17.5 (700)
- Notes
Isotropic, but locally slightly anisotropic. The type description gives a higher reflectivity, with a mean value of ~23.5%.
PPL intrinsic colour; no change on stage rotation
XPL extinct at every orientation
Crystallography
- Space group
- #222
- Cell parameters
- a = 8.297 Å · b = 2 Å
- Z
- 8
- Morphology
As subhedral crystals, less than 1 mm in size. Also as exsolution lamellae along (111) in magnetite.
- Type-locality form
Occurs along octahedral planes in magnetite and less commonly as subhedral isolated crystals.
Crystal structure
Chemical composition
Synonyms
- Coulsoniet
In other languages
- German
- Coulsonit · Vanadomagnetit
- Italian
- Coulsonite
- Russian
- Кульсонит
Classification
Strunz
10th ed.4.BB.05
- 4OxidesClass
- 4.BMetal: Oxygen = 3:4 and similarDivision
- 4.BBWith only medium-sized cationsGroup
- 4.BB.05CoulsoniteSpecies
Dana
8th ed.07.02.04.02
- 07Multiple OxidesClass
- 07.02AB2X4Type
- 07.02.04(Vanadium subgroup)Group
- 07.02.04.02CoulsoniteSpecies
CIM
—7.12.19
- 7Oxides and HydroxidesClass
- 7.12Oxides of V, Nb and TaGroup
- 7.12.19CoulsoniteSpecies
Group, growth & confusion
Literature, links & citation
Citations
- 1937Dunn, J.A. (1937) Coulsonite. Memoirs of the Geological Survey of India: 69: 21-21.
- 1937Dunn and Dey (1937) Mining Geol. Institute of India, Transactions: 31: 131.
- 1951Wyckoff, R.W.G. (1951) Crystal Structures, Vol 2. New York: Interscience Publishers, pg 43.
- 1954Richardson, H.M., Ball, F., Rigby, G.R. (1954) The preparation and properties of vanadium spinels. Transactions of the British Ceramic Society, 53, 376-387.
- 1962Radtke, Arthur S. (1962) Coulsonite, FeV2O4, a spinel-type mineral from Lovelock, Nevada. American Mineralogist, 47 (11-12) 1284-1291
Cite this entry
@misc{mineral2026,
author = {Mineral Index editorial board},
title = {Coulsonite — Mineral Index},
year = {2026},
url = {https://mineralindex.org/minerals/coulsonite-1142},
note = {Accessed 2026-05-11}
}